diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 777d16a07..945b46ae0 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -65,7 +65,7 @@ jobs:
           make ${{ matrix.scenario}}
 
       - name: Publish coverage
-        uses: codecov/codecov-action@v4
+        uses: codecov/codecov-action@v3
         with:
           file: ./coverage.txt
 
diff --git a/app/vmauth/auth_config.go b/app/vmauth/auth_config.go
index 43b40bc94..fbb9bb414 100644
--- a/app/vmauth/auth_config.go
+++ b/app/vmauth/auth_config.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/base64"
 	"flag"
 	"fmt"
@@ -290,6 +291,13 @@ func (sp *SrcPath) MarshalYAML() (interface{}, error) {
 	return sp.sOriginal, nil
 }
 
+var (
+	configReloads      = metrics.NewCounter(`vmauth_config_last_reload_total`)
+	configReloadErrors = metrics.NewCounter(`vmauth_config_last_reload_errors_total`)
+	configSuccess      = metrics.NewCounter(`vmauth_config_last_reload_successful`)
+	configTimestamp    = metrics.NewCounter(`vmauth_config_last_reload_success_timestamp_seconds`)
+)
+
 func initAuthConfig() {
 	if len(*authConfigPath) == 0 {
 		logger.Fatalf("missing required `-auth.config` command-line flag")
@@ -300,11 +308,14 @@ func initAuthConfig() {
 	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1240
 	sighupCh := procutil.NewSighupChan()
 
-	err := loadAuthConfig()
+	_, err := loadAuthConfig()
 	if err != nil {
 		logger.Fatalf("cannot load auth config: %s", err)
 	}
 
+	configSuccess.Set(1)
+	configTimestamp.Set(fasttime.UnixTimestamp())
+
 	stopCh = make(chan struct{})
 	authConfigWG.Add(1)
 	go func() {
@@ -327,52 +338,75 @@ func authConfigReloader(sighupCh <-chan os.Signal) {
 		refreshCh = ticker.C
 	}
 
+	updateFn := func() {
+		configReloads.Inc()
+		updated, err := loadAuthConfig()
+		if err != nil {
+			logger.Errorf("failed to load auth config; using the last successfully loaded config; error: %s", err)
+			configSuccess.Set(0)
+			configReloadErrors.Inc()
+			return
+		}
+		configSuccess.Set(1)
+		if updated {
+			configTimestamp.Set(fasttime.UnixTimestamp())
+		}
+	}
+
 	for {
 		select {
 		case <-stopCh:
 			return
 		case <-refreshCh:
-			procutil.SelfSIGHUP()
+			updateFn()
 		case <-sighupCh:
 			logger.Infof("SIGHUP received; loading -auth.config=%q", *authConfigPath)
-			err := loadAuthConfig()
-			if err != nil {
-				logger.Errorf("failed to load auth config; using the last successfully loaded config; error: %s", err)
-				continue
-			}
+			updateFn()
 		}
 	}
 }
 
+// authConfigData stores the yaml definition for this config.
+// authConfigData needs to be updated each time authConfig is updated.
+var authConfigData atomic.Pointer[[]byte]
+
 var authConfig atomic.Pointer[AuthConfig]
 var authUsers atomic.Pointer[map[string]*UserInfo]
 var authConfigWG sync.WaitGroup
 var stopCh chan struct{}
 
-func loadAuthConfig() error {
-	ac, err := readAuthConfig(*authConfigPath)
+// loadAuthConfig loads and applies the config from *authConfigPath.
+// It returns bool value to identify if new config was applied.
+// The config can be not applied if there is a parsing error
+// or if there are no changes to the current authConfig.
+func loadAuthConfig() (bool, error) {
+	data, err := fs.ReadFileOrHTTP(*authConfigPath)
 	if err != nil {
-		return fmt.Errorf("failed to load -auth.config=%q: %s", *authConfigPath, err)
+		return false, fmt.Errorf("failed to read -auth.config=%q: %w", *authConfigPath, err)
+	}
+
+	oldData := authConfigData.Load()
+	if oldData != nil && bytes.Equal(data, *oldData) {
+		// there are no updates in the config - skip reloading.
+		return false, nil
+	}
+
+	ac, err := parseAuthConfig(data)
+	if err != nil {
+		return false, fmt.Errorf("failed to parse -auth.config=%q: %w", *authConfigPath, err)
 	}
 
 	m, err := parseAuthConfigUsers(ac)
 	if err != nil {
-		return fmt.Errorf("failed to parse users from -auth.config=%q: %s", *authConfigPath, err)
+		return false, fmt.Errorf("failed to parse users from -auth.config=%q: %w", *authConfigPath, err)
 	}
 	logger.Infof("loaded information about %d users from -auth.config=%q", len(m), *authConfigPath)
 
 	authConfig.Store(ac)
+	authConfigData.Store(&data)
 	authUsers.Store(&m)
 
-	return nil
-}
-
-func readAuthConfig(path string) (*AuthConfig, error) {
-	data, err := fs.ReadFileOrHTTP(path)
-	if err != nil {
-		return nil, err
-	}
-	return parseAuthConfig(data)
+	return true, nil
 }
 
 func parseAuthConfig(data []byte) (*AuthConfig, error) {
diff --git a/app/vmbackup/README.md b/app/vmbackup/README.md
index 9daad41f1..340c99d6b 100644
--- a/app/vmbackup/README.md
+++ b/app/vmbackup/README.md
@@ -143,20 +143,23 @@ See [this article](https://medium.com/@valyala/speeding-up-backups-for-big-time-
 
 ## Advanced usage
 
-* Obtaining credentials from a file.
 
-  Add flag `-credsFilePath=/etc/credentials` with the following content:
+### Providing credentials as a file
 
-    for s3 (aws, minio or other s3 compatible storages):
+Obtaining credentials from a file.
 
+Add flag `-credsFilePath=/etc/credentials` with the following content:
+
+- for S3 (AWS, MinIO or other S3 compatible storages):
+    
      ```console
      [default]
      aws_access_key_id=theaccesskey
      aws_secret_access_key=thesecretaccesskeyvalue
     ```
 
-    for gce cloud storage:
-
+- for GCP cloud storage:
+    
     ```json
     {
            "type": "service_account",
@@ -171,24 +174,99 @@ See [this article](https://medium.com/@valyala/speeding-up-backups-for-big-time-
            "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/service-account-email"
     }
     ```
-* Obtaining credentials from env variables.
-    - For AWS S3 compatible storages set env variable `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`.
-      Also you can set env variable `AWS_SHARED_CREDENTIALS_FILE` with path to credentials file.
-    - For GCE cloud storage set env variable `GOOGLE_APPLICATION_CREDENTIALS` with path to credentials file.
-    - For Azure storage either set env variables `AZURE_STORAGE_ACCOUNT_NAME` and `AZURE_STORAGE_ACCOUNT_KEY`, or `AZURE_STORAGE_ACCOUNT_CONNECTION_STRING`.
 
-* Usage with s3 custom url endpoint. It is possible to use `vmbackup` with s3 compatible storages like minio, cloudian, etc.
-  You have to add a custom url endpoint via flag:
+### Providing credentials via env variables 
 
-```console
-  # for minio
-  -customS3Endpoint=http://localhost:9000
+Obtaining credentials from env variables.
+- For AWS S3 compatible storages set env variable `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`. 
+  Also you can set env variable `AWS_SHARED_CREDENTIALS_FILE` with path to credentials file.
+- For GCE cloud storage set env variable `GOOGLE_APPLICATION_CREDENTIALS` with path to credentials file.
+- For Azure storage either set env variables `AZURE_STORAGE_ACCOUNT_NAME` and `AZURE_STORAGE_ACCOUNT_KEY`, or `AZURE_STORAGE_ACCOUNT_CONNECTION_STRING`.
 
-  # for aws gov region
-  -customS3Endpoint=https://s3-fips.us-gov-west-1.amazonaws.com
+Please, note that `vmbackup` will use credentials provided by cloud providers metadata service [when applicable](https://docs.victoriametrics.com/vmbackup.html#using-cloud-providers-metadata-service).
+
+### Using cloud providers metadata service
+
+`vmbackup` and `vmbackupmanager` will automatically use cloud providers metadata service in order to obtain credentials if they are running in cloud environment
+and credentials are not explicitly provided via flags or env variables.
+
+### Providing credentials in Kubernetes
+
+The simplest way to provide credentials in Kubernetes is to use [Secrets](https://kubernetes.io/docs/concepts/configuration/secret/)
+and inject them into the pod as environment variables. For example, the following secret can be used for AWS S3 credentials:
+```yaml
+apiVersion: v1
+kind: Secret
+metadata:
+  name: vmbackup-credentials
+data:
+  access_key: key
+  secret_key: secret
+```
+And then it can be injected into the pod as environment variables:
+```yaml
+...
+env:
+- name: AWS_ACCESS_KEY_ID
+  valueFrom:
+    secretKeyRef:
+      key: access_key
+      name: vmbackup-credentials
+- name: AWS_SECRET_ACCESS_KEY
+  valueFrom:
+    secretKeyRef:
+      key: secret_key
+      name: vmbackup-credentials
+...
 ```
 
-* Run `vmbackup -help` in order to see all the available options:
+A more secure way is to use IAM roles to provide tokens for pods instead of managing credentials manually. 
+
+For AWS deployments it will be required to configure [IAM roles for service accounts](https://docs.aws.amazon.com/eks/latest/userguide/iam-roles-for-service-accounts.html).
+In order to use IAM roles for service accounts with `vmbackup` or `vmbackupmanager` it is required to create ServiceAccount with IAM role mapping:
+```yaml
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: monitoring-backups
+  annotations:
+    eks.amazonaws.com/role-arn: arn:aws:iam::{ACCOUNT_ID}:role/{ROLE_NAME}
+```
+And [configure pod to use service account](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/).
+After this `vmbackup` and `vmbackupmanager` will automatically use IAM role for service account in order to obtain credentials.
+
+For GCP deployments it will be required to configure [Workload Identity](https://cloud.google.com/kubernetes-engine/docs/how-to/workload-identity).
+In order to use Workload Identity with `vmbackup` or `vmbackupmanager` it is required to create ServiceAccount with Workload Identity annotation:
+```yaml
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: monitoring-backups
+  annotations:
+    iam.gke.io/gcp-service-account: {sa_name}@{project_name}.iam.gserviceaccount.com
+```
+And [configure pod to use service account](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/).
+After this `vmbackup` and `vmbackupmanager` will automatically use Workload Identity for servicpe account in order to obtain credentials.
+
+### Using custom S3 endpoint
+
+Usage with s3 custom url endpoint. It is possible to use `vmbackup` with s3 compatible storages like minio, cloudian, etc.
+You have to add a custom url endpoint via flag:
+
+- for MinIO
+    ```console
+      -customS3Endpoint=http://localhost:9000
+    ```
+
+- for aws gov region
+    ```console
+      -customS3Endpoint=https://s3-fips.us-gov-west-1.amazonaws.com
+    ```
+
+### Command-line flags
+
+Run `vmbackup -help` in order to see all the available options:
 
 ```console
   -concurrency int
diff --git a/app/vmbackupmanager/README.md b/app/vmbackupmanager/README.md
index 4d0c1937a..f56cac238 100644
--- a/app/vmbackupmanager/README.md
+++ b/app/vmbackupmanager/README.md
@@ -110,6 +110,9 @@ The result on the GCS bucket
 
   <img alt="latest folder" src="vmbackupmanager_latest_folder.png">
 
+Please, see [vmbackup docs](https://docs.victoriametrics.com/vmbackup.html#advanced-usage) for more examples of authentication with different
+storage types.
+
 ## Backup Retention Policy
 
 Backup retention policy is controlled by:
diff --git a/dashboards/victoriametrics.json b/dashboards/victoriametrics.json
index 69a0d93b5..2d6313523 100644
--- a/dashboards/victoriametrics.json
+++ b/dashboards/victoriametrics.json
@@ -76,7 +76,7 @@
           "uid": "$ds"
         },
         "enable": true,
-        "expr": "sum(vm_app_version{job=~\"$job\"}) by(short_version) unless (sum(vm_app_version{job=~\"$job\"} offset 20m) by(short_version))",
+        "expr": "sum(vm_app_version{job=~\"$job\", instance=~\"$instance\"}) by(short_version) unless (sum(vm_app_version{job=~\"$job\", instance=~\"$instance\"} offset 20m) by(short_version))",
         "hide": true,
         "iconColor": "dark-blue",
         "name": "version",
diff --git a/dashboards/vm/victoriametrics.json b/dashboards/vm/victoriametrics.json
index 52c04c949..161308ade 100644
--- a/dashboards/vm/victoriametrics.json
+++ b/dashboards/vm/victoriametrics.json
@@ -77,7 +77,7 @@
           "uid": "$ds"
         },
         "enable": true,
-        "expr": "sum(vm_app_version{job=~\"$job\"}) by(short_version) unless (sum(vm_app_version{job=~\"$job\"} offset 20m) by(short_version))",
+        "expr": "sum(vm_app_version{job=~\"$job\", instance=~\"$instance\"}) by(short_version) unless (sum(vm_app_version{job=~\"$job\", instance=~\"$instance\"} offset 20m) by(short_version))",
         "hide": true,
         "iconColor": "dark-blue",
         "name": "version",
diff --git a/docs/Articles.md b/docs/Articles.md
index 9e7e679ea..8cb903c6e 100644
--- a/docs/Articles.md
+++ b/docs/Articles.md
@@ -78,6 +78,7 @@ See also [case studies](https://docs.victoriametrics.com/CaseStudies.html).
 * [VictoriaMetrics: an overview and its use instead of Prometheus](https://rtfm.co.ua/en/victoriametrics-an-overview-and-its-use-instead-of-prometheus/)
 * [VictoriaMetrics: deploying a Kubernetes monitoring stack](https://rtfm.co.ua/en/victoriametrics-deploying-a-kubernetes-monitoring-stack/)
 * [Better, Faster, Cheaper: How Grammarly Improved Monitoring by Over 10x with VictoriaMetrics](https://www.grammarly.com/blog/engineering/monitoring-with-victoriametrics/)
+* [VictoriaMetrics, a stress-free Prometheus Remote Storage for 1 Billion metrics](https://medium.com/criteo-engineering/victoriametrics-a-prometheus-remote-storage-solution-57081a3d8e61)
 
 ## Our articles
 
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 1f0e5b6d8..8895b361d 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -38,20 +38,31 @@ The following `tip` changes can be tested by building VictoriaMetrics components
 * FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): improve accessibility score to 100 according to [Google's Lighthouse](https://developer.chrome.com/docs/lighthouse/accessibility/) tests.
 * FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): organize `min`, `max`, `median` values on the chart legend and tooltips for better visibility.
 * FEATURE: dashboards: provide copies of Grafana dashboards alternated with VictoriaMetrics datasource at [dashboards/vm](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/dashboards/vm).
-* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): added ability to set, override and clear request and response headers on a per-user and per-path basis. See [this i
-ssue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4825) and [these docs](https://docs.victoriametrics.com/vmauth.html#auth-config) for details.
+* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): added ability to set, override and clear request and response headers on a per-user and per-path basis. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4825) and [these docs](https://docs.victoriametrics.com/vmauth.html#auth-config) for details.
 * FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): add ability to retry requests to the [remaining backends](https://docs.victoriametrics.com/vmauth.html#load-balancing) if they return response status codes specified in the `retry_status_codes` list. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4893).
+* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): expose metrics `vmauth_config_last_reload_*` for tracking the state of config reloads, similarly to vmagent/vmalert components.
+* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): do not print logs like `SIGHUP received...` once per configured `-configCheckInterval` cmd-line flag. This log will be printed only if config reload was invoked manually. 
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): add `eval_offset` attribute for [Groups](https://docs.victoriametrics.com/vmalert.html#groups). If specified, Group will be evaluated at the exact time offset on the range of [0...evaluationInterval]. The setting might be useful for cron-like rules which must be evaluated at specific moments of time. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3409) for details.
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): validate [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html) function names in alerting and recording rules when `vmalert` runs with `-dryRun` command-line flag. Previously it was allowed to use unknown (aka invalid) MetricsQL function names there. For example, `foo()` was counted as a valid query. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4933).
 * FEATURE: limit the length of string params in log messages to 500 chars. Longer string params are replaced with the `first_250_chars..last_250_chars`. This prevents from too long log lines, which can be emitted by VictoriaMetrics components.
 
-* BUGFIX: [storage](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html): prevent from livelock when [forced merge](https://docs.victoriametrics.com/#forced-merge) is called under high data ingestion. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4987).
-* BUGFIX: [Graphite Render API](https://docs.victoriametrics.com/#graphite-render-api-usage): correctly return `null` instead of `Inf` in JSON query responses. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3783).
 * BUGFIX: [Official Grafana dashboards for VictoriaMetrics](https://grafana.com/orgs/victoriametrics): fix display of ingested rows rate for `Samples ingested/s` and `Samples rate` panels for vmagent's dasbhoard. Previously, not all ingested protocols were accounted in these panels. An extra panel `Rows rate` was added to `Ingestion` section to display the split for rows ingested rate by protocol.
 * BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix the bug causing render looping when switching to heatmap.
-* BUGFIX: [vmbackup](https://docs.victoriametrics.com/vmbackup.html): properly copy `parts.json` files inside `<-storageDataPath>/{data,indexdb}` folders during [incremental backups](https://docs.victoriametrics.com/vmbackup.html#incremental-backups). Previously the new `parts.json` could be skipped during incremental backups, which could lead to inability to restore from the backup. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5005). This issue has been introduced in [v1.90.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.90.0).
 * BUGFIX: [VictoriaMetrics enterprise](https://docs.victoriametrics.com/enterprise.html) validate `-dedup.minScrapeInterval` value and `-downsampling.period` intervals are multiples of each other. See [these docs](https://docs.victoriametrics.com/#downsampling).
+* BUGFIX: [vmbackup](https://docs.victoriametrics.com/vmbackup.html): properly copy `appliedRetention.txt` files inside `<-storageDataPath>/{data}` folders during [incremental backups](https://docs.victoriametrics.com/vmbackup.html#incremental-backups). Previously the new `appliedRetention.txt` could be skipped during incremental backups, which could lead to increased load on storage after restoring from backup. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5005).
+
+## [v1.93.5](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.93.5)
+
+Released at 2023-09-19
+
+**v1.93.x is a line of LTS releases (e.g. long-time support). It contains important up-to-date bugfixes.
+The v1.93.x line will be supported for at least 12 months since [v1.93.0](https://docs.victoriametrics.com/CHANGELOG.html#v1930) release**
+
+* BUGFIX: [storage](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html): prevent from livelock when [forced merge](https://docs.victoriametrics.com/#forced-merge) is called under high data ingestion. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4987).
+* BUGFIX: [Graphite Render API](https://docs.victoriametrics.com/#graphite-render-api-usage): correctly return `null` instead of `Inf` in JSON query responses. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3783).
+* BUGFIX: [vmbackup](https://docs.victoriametrics.com/vmbackup.html): properly copy `parts.json` files inside `<-storageDataPath>/{data,indexdb}` folders during [incremental backups](https://docs.victoriametrics.com/vmbackup.html#incremental-backups). Previously the new `parts.json` could be skipped during incremental backups, which could lead to inability to restore from the backup. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5005). This issue has been introduced in [v1.90.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.90.0).
 * BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): properly close connections to Kubernetes API server after the change in `selectors` or `namespaces` sections of [kubernetes_sd_configs](https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs). Previously `vmagent` could continue polling Kubernetes API server with the old `selectors` or `namespaces` configs additionally to polling new configs. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4850).
+* BUGFIX: [vmauth](https://docs.victoriametrics.com/vmauth.html): prevent configuration reloading if there were no changes in config. This improves memory usage when `-configCheckInterval` cmd-line flag is configured and config has extensive list of regexp expressions requiring additional memory on parsing. 
 
 ## [v1.93.4](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.93.4)
 
diff --git a/docs/operator/vars.md b/docs/operator/vars.md
index dad003d18..edf6939e4 100644
--- a/docs/operator/vars.md
+++ b/docs/operator/vars.md
@@ -10,7 +10,7 @@ aliases:
 - /operator/vars.html
 ---
 # Auto Generated vars for package config 
- updated at Wed Sep 13 14:05:24 UTC 2023 
+ updated at Thu Sep 21 10:01:40 UTC 2023 
 
 
 | varible name | variable default value | variable required | variable description |
@@ -20,7 +20,7 @@ aliases:
 | VM_CUSTOMCONFIGRELOADERIMAGE | victoriametrics/operator:config-reloader-v0.32.0 | false | - |
 | VM_PSPAUTOCREATEENABLED | false | false | - |
 | VM_VMALERTDEFAULT_IMAGE | victoriametrics/vmalert | false | - |
-| VM_VMALERTDEFAULT_VERSION | v1.93.4 | false | - |
+| VM_VMALERTDEFAULT_VERSION | v1.93.5 | false | - |
 | VM_VMALERTDEFAULT_PORT | 8080 | false | - |
 | VM_VMALERTDEFAULT_USEDEFAULTRESOURCES | true | false | - |
 | VM_VMALERTDEFAULT_RESOURCE_LIMIT_MEM | 500Mi | false | - |
@@ -31,7 +31,7 @@ aliases:
 | VM_VMALERTDEFAULT_CONFIGRELOADERMEMORY | 25Mi | false | - |
 | VM_VMALERTDEFAULT_CONFIGRELOADIMAGE | jimmidyson/configmap-reload:v0.3.0 | false | - |
 | VM_VMAGENTDEFAULT_IMAGE | victoriametrics/vmagent | false | - |
-| VM_VMAGENTDEFAULT_VERSION | v1.93.4 | false | - |
+| VM_VMAGENTDEFAULT_VERSION | v1.93.5 | false | - |
 | VM_VMAGENTDEFAULT_CONFIGRELOADIMAGE | quay.io/prometheus-operator/prometheus-config-reloader:v0.68.0 | false | - |
 | VM_VMAGENTDEFAULT_PORT | 8429 | false | - |
 | VM_VMAGENTDEFAULT_USEDEFAULTRESOURCES | true | false | - |
@@ -42,7 +42,7 @@ aliases:
 | VM_VMAGENTDEFAULT_CONFIGRELOADERCPU | 100m | false | - |
 | VM_VMAGENTDEFAULT_CONFIGRELOADERMEMORY | 25Mi | false | - |
 | VM_VMSINGLEDEFAULT_IMAGE | victoriametrics/victoria-metrics | false | - |
-| VM_VMSINGLEDEFAULT_VERSION | v1.93.4 | false | - |
+| VM_VMSINGLEDEFAULT_VERSION | v1.93.5 | false | - |
 | VM_VMSINGLEDEFAULT_PORT | 8429 | false | - |
 | VM_VMSINGLEDEFAULT_USEDEFAULTRESOURCES | true | false | - |
 | VM_VMSINGLEDEFAULT_RESOURCE_LIMIT_MEM | 1500Mi | false | - |
@@ -53,14 +53,14 @@ aliases:
 | VM_VMSINGLEDEFAULT_CONFIGRELOADERMEMORY | 25Mi | false | - |
 | VM_VMCLUSTERDEFAULT_USEDEFAULTRESOURCES | true | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_IMAGE | victoriametrics/vmselect | false | - |
-| VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_VERSION | v1.93.4-cluster | false | - |
+| VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_VERSION | v1.93.5-cluster | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_PORT | 8481 | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_RESOURCE_LIMIT_MEM | 1000Mi | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_RESOURCE_LIMIT_CPU | 500m | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_RESOURCE_REQUEST_MEM | 500Mi | false | - |
 | VM_VMCLUSTERDEFAULT_VMSELECTDEFAULT_RESOURCE_REQUEST_CPU | 100m | false | - |
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_IMAGE | victoriametrics/vmstorage | false | - |
-| VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_VERSION | v1.93.4-cluster | false | - |
+| VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_VERSION | v1.93.5-cluster | false | - |
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_VMINSERTPORT | 8400 | false | - |
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_VMSELECTPORT | 8401 | false | - |
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_PORT | 8482 | false | - |
@@ -69,7 +69,7 @@ aliases:
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_RESOURCE_REQUEST_MEM | 500Mi | false | - |
 | VM_VMCLUSTERDEFAULT_VMSTORAGEDEFAULT_RESOURCE_REQUEST_CPU | 250m | false | - |
 | VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_IMAGE | victoriametrics/vminsert | false | - |
-| VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_VERSION | v1.93.4-cluster | false | - |
+| VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_VERSION | v1.93.5-cluster | false | - |
 | VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_PORT | 8480 | false | - |
 | VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_RESOURCE_LIMIT_MEM | 500Mi | false | - |
 | VM_VMCLUSTERDEFAULT_VMINSERTDEFAULT_RESOURCE_LIMIT_CPU | 500m | false | - |
@@ -88,7 +88,7 @@ aliases:
 | VM_VMALERTMANAGER_RESOURCE_REQUEST_CPU | 30m | false | - |
 | VM_DISABLESELFSERVICESCRAPECREATION | false | false | - |
 | VM_VMBACKUP_IMAGE | victoriametrics/vmbackupmanager | false | - |
-| VM_VMBACKUP_VERSION | v1.93.4-enterprise | false | - |
+| VM_VMBACKUP_VERSION | v1.93.5-enterprise | false | - |
 | VM_VMBACKUP_PORT | 8300 | false | - |
 | VM_VMBACKUP_USEDEFAULTRESOURCES | true | false | - |
 | VM_VMBACKUP_RESOURCE_LIMIT_MEM | 500Mi | false | - |
@@ -97,7 +97,7 @@ aliases:
 | VM_VMBACKUP_RESOURCE_REQUEST_CPU | 150m | false | - |
 | VM_VMBACKUP_LOGLEVEL | INFO | false | - |
 | VM_VMAUTHDEFAULT_IMAGE | victoriametrics/vmauth | false | - |
-| VM_VMAUTHDEFAULT_VERSION | v1.93.4 | false | - |
+| VM_VMAUTHDEFAULT_VERSION | v1.93.5 | false | - |
 | VM_VMAUTHDEFAULT_CONFIGRELOADIMAGE | quay.io/prometheus-operator/prometheus-config-reloader:v0.68.0 | false | - |
 | VM_VMAUTHDEFAULT_PORT | 8427 | false | - |
 | VM_VMAUTHDEFAULT_USEDEFAULTRESOURCES | true | false | - |
diff --git a/docs/vmbackup.md b/docs/vmbackup.md
index 39c4b3e95..bff38459a 100644
--- a/docs/vmbackup.md
+++ b/docs/vmbackup.md
@@ -154,20 +154,23 @@ See [this article](https://medium.com/@valyala/speeding-up-backups-for-big-time-
 
 ## Advanced usage
 
-* Obtaining credentials from a file.
 
-  Add flag `-credsFilePath=/etc/credentials` with the following content:
+### Providing credentials as a file
 
-    for s3 (aws, minio or other s3 compatible storages):
+Obtaining credentials from a file.
 
+Add flag `-credsFilePath=/etc/credentials` with the following content:
+
+- for S3 (AWS, MinIO or other S3 compatible storages):
+    
      ```console
      [default]
      aws_access_key_id=theaccesskey
      aws_secret_access_key=thesecretaccesskeyvalue
     ```
 
-    for gce cloud storage:
-
+- for GCP cloud storage:
+    
     ```json
     {
            "type": "service_account",
@@ -182,24 +185,99 @@ See [this article](https://medium.com/@valyala/speeding-up-backups-for-big-time-
            "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/service-account-email"
     }
     ```
-* Obtaining credentials from env variables.
-    - For AWS S3 compatible storages set env variable `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`.
-      Also you can set env variable `AWS_SHARED_CREDENTIALS_FILE` with path to credentials file.
-    - For GCE cloud storage set env variable `GOOGLE_APPLICATION_CREDENTIALS` with path to credentials file.
-    - For Azure storage either set env variables `AZURE_STORAGE_ACCOUNT_NAME` and `AZURE_STORAGE_ACCOUNT_KEY`, or `AZURE_STORAGE_ACCOUNT_CONNECTION_STRING`.
 
-* Usage with s3 custom url endpoint. It is possible to use `vmbackup` with s3 compatible storages like minio, cloudian, etc.
-  You have to add a custom url endpoint via flag:
+### Providing credentials via env variables 
 
-```console
-  # for minio
-  -customS3Endpoint=http://localhost:9000
+Obtaining credentials from env variables.
+- For AWS S3 compatible storages set env variable `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`. 
+  Also you can set env variable `AWS_SHARED_CREDENTIALS_FILE` with path to credentials file.
+- For GCE cloud storage set env variable `GOOGLE_APPLICATION_CREDENTIALS` with path to credentials file.
+- For Azure storage either set env variables `AZURE_STORAGE_ACCOUNT_NAME` and `AZURE_STORAGE_ACCOUNT_KEY`, or `AZURE_STORAGE_ACCOUNT_CONNECTION_STRING`.
 
-  # for aws gov region
-  -customS3Endpoint=https://s3-fips.us-gov-west-1.amazonaws.com
+Please, note that `vmbackup` will use credentials provided by cloud providers metadata service [when applicable](https://docs.victoriametrics.com/vmbackup.html#using-cloud-providers-metadata-service).
+
+### Using cloud providers metadata service
+
+`vmbackup` and `vmbackupmanager` will automatically use cloud providers metadata service in order to obtain credentials if they are running in cloud environment
+and credentials are not explicitly provided via flags or env variables.
+
+### Providing credentials in Kubernetes
+
+The simplest way to provide credentials in Kubernetes is to use [Secrets](https://kubernetes.io/docs/concepts/configuration/secret/)
+and inject them into the pod as environment variables. For example, the following secret can be used for AWS S3 credentials:
+```yaml
+apiVersion: v1
+kind: Secret
+metadata:
+  name: vmbackup-credentials
+data:
+  access_key: key
+  secret_key: secret
+```
+And then it can be injected into the pod as environment variables:
+```yaml
+...
+env:
+- name: AWS_ACCESS_KEY_ID
+  valueFrom:
+    secretKeyRef:
+      key: access_key
+      name: vmbackup-credentials
+- name: AWS_SECRET_ACCESS_KEY
+  valueFrom:
+    secretKeyRef:
+      key: secret_key
+      name: vmbackup-credentials
+...
 ```
 
-* Run `vmbackup -help` in order to see all the available options:
+A more secure way is to use IAM roles to provide tokens for pods instead of managing credentials manually. 
+
+For AWS deployments it will be required to configure [IAM roles for service accounts](https://docs.aws.amazon.com/eks/latest/userguide/iam-roles-for-service-accounts.html).
+In order to use IAM roles for service accounts with `vmbackup` or `vmbackupmanager` it is required to create ServiceAccount with IAM role mapping:
+```yaml
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: monitoring-backups
+  annotations:
+    eks.amazonaws.com/role-arn: arn:aws:iam::{ACCOUNT_ID}:role/{ROLE_NAME}
+```
+And [configure pod to use service account](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/).
+After this `vmbackup` and `vmbackupmanager` will automatically use IAM role for service account in order to obtain credentials.
+
+For GCP deployments it will be required to configure [Workload Identity](https://cloud.google.com/kubernetes-engine/docs/how-to/workload-identity).
+In order to use Workload Identity with `vmbackup` or `vmbackupmanager` it is required to create ServiceAccount with Workload Identity annotation:
+```yaml
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: monitoring-backups
+  annotations:
+    iam.gke.io/gcp-service-account: {sa_name}@{project_name}.iam.gserviceaccount.com
+```
+And [configure pod to use service account](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/).
+After this `vmbackup` and `vmbackupmanager` will automatically use Workload Identity for servicpe account in order to obtain credentials.
+
+### Using custom S3 endpoint
+
+Usage with s3 custom url endpoint. It is possible to use `vmbackup` with s3 compatible storages like minio, cloudian, etc.
+You have to add a custom url endpoint via flag:
+
+- for MinIO
+    ```console
+      -customS3Endpoint=http://localhost:9000
+    ```
+
+- for aws gov region
+    ```console
+      -customS3Endpoint=https://s3-fips.us-gov-west-1.amazonaws.com
+    ```
+
+### Command-line flags
+
+Run `vmbackup -help` in order to see all the available options:
 
 ```console
   -concurrency int
diff --git a/docs/vmbackupmanager.md b/docs/vmbackupmanager.md
index 7f912ff9e..051c87656 100644
--- a/docs/vmbackupmanager.md
+++ b/docs/vmbackupmanager.md
@@ -121,6 +121,9 @@ The result on the GCS bucket
 
   <img alt="latest folder" src="vmbackupmanager_latest_folder.png">
 
+Please, see [vmbackup docs](https://docs.victoriametrics.com/vmbackup.html#advanced-usage) for more examples of authentication with different
+storage types.
+
 ## Backup Retention Policy
 
 Backup retention policy is controlled by:
diff --git a/lib/backup/common/part.go b/lib/backup/common/part.go
index d7f9aa239..8b9c68e31 100644
--- a/lib/backup/common/part.go
+++ b/lib/backup/common/part.go
@@ -40,9 +40,11 @@ type Part struct {
 
 // key returns a string, which uniquely identifies p.
 func (p *Part) key() string {
-	if strings.HasSuffix(p.Path, "/parts.json") {
-		// parts.json file contents changes over time, so it must have an unique key in order
-		// to always copy it during backup, restore and server-side copy.
+	if strings.HasSuffix(p.Path, "/parts.json") ||
+		strings.HasSuffix(p.Path, "/appliedRetention.txt") {
+		// parts.json and appliedRetention.txt files contents changes over time,
+		// so it must have an unique key in order to always copy it during
+		// backup, restore and server-side copy.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5005
 		id := atomic.AddUint64(&uniqueKeyID, 1)
 		return fmt.Sprintf("unique-%016X", id)
diff --git a/lib/logstorage/datadb.go b/lib/logstorage/datadb.go
index d23c05eed..41f9c31a6 100644
--- a/lib/logstorage/datadb.go
+++ b/lib/logstorage/datadb.go
@@ -149,7 +149,18 @@ func mustOpenDatadb(pt *partition, path string, flushInterval time.Duration) *da
 
 	pws := make([]*partWrapper, len(partNames))
 	for i, partName := range partNames {
+		// Make sure the partName exists on disk.
+		// If it is missing, then manual action from the user is needed,
+		// since this is unexpected state, which cannot occur under normal operation,
+		// including unclean shutdown.
 		partPath := filepath.Join(path, partName)
+		if !fs.IsPathExist(partPath) {
+			partsFile := filepath.Join(path, partsFilename)
+			logger.Panicf("FATAL: part %q is listed in %q, but is missing on disk; "+
+				"ensure %q contents is not corrupted; remove %q to rebuild its' content from the list of existing parts",
+				partPath, partsFile, partsFile, partsFile)
+		}
+
 		p := mustOpenFilePart(pt, partPath)
 		pws[i] = newPartWrapper(p, nil, time.Time{})
 	}
diff --git a/lib/mergeset/table.go b/lib/mergeset/table.go
index 8b916770e..bf7274a8e 100644
--- a/lib/mergeset/table.go
+++ b/lib/mergeset/table.go
@@ -1349,6 +1349,18 @@ func mustOpenParts(path string) []*partWrapper {
 	des := fs.MustReadDir(path)
 	m := make(map[string]struct{}, len(partNames))
 	for _, partName := range partNames {
+		// Make sure the partName exists on disk.
+		// If it is missing, then manual action from the user is needed,
+		// since this is unexpected state, which cannot occur under normal operation,
+		// including unclean shutdown.
+		partPath := filepath.Join(path, partName)
+		if !fs.IsPathExist(partPath) {
+			partsFile := filepath.Join(path, partsFilename)
+			logger.Panicf("FATAL: part %q is listed in %q, but is missing on disk; "+
+				"ensure %q contents is not corrupted; remove %q to rebuild its' content from the list of existing parts",
+				partPath, partsFile, partsFile, partsFile)
+		}
+
 		m[partName] = struct{}{}
 	}
 	for _, de := range des {
diff --git a/lib/storage/index_db.go b/lib/storage/index_db.go
index dd4c54b75..62777d7fa 100644
--- a/lib/storage/index_db.go
+++ b/lib/storage/index_db.go
@@ -668,7 +668,8 @@ func (is *indexSearch) searchLabelNamesWithFiltersOnDate(qt *querytracer.Tracer,
 		// This would help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
 		metricIDs := filter.AppendTo(nil)
 		qt.Printf("sort %d metricIDs", len(metricIDs))
-		return is.getLabelNamesForMetricIDs(qt, metricIDs, lns, maxLabelNames)
+		is.getLabelNamesForMetricIDs(qt, metricIDs, lns, maxLabelNames)
+		return nil
 	}
 	var prevLabelName []byte
 	ts := &is.ts
@@ -732,39 +733,34 @@ func (is *indexSearch) searchLabelNamesWithFiltersOnDate(qt *querytracer.Tracer,
 	return nil
 }
 
-func (is *indexSearch) getLabelNamesForMetricIDs(qt *querytracer.Tracer, metricIDs []uint64, lns map[string]struct{}, maxLabelNames int) error {
+func (is *indexSearch) getLabelNamesForMetricIDs(qt *querytracer.Tracer, metricIDs []uint64, lns map[string]struct{}, maxLabelNames int) {
 	lns["__name__"] = struct{}{}
 	var mn MetricName
 	foundLabelNames := 0
 	var buf []byte
 	for _, metricID := range metricIDs {
-		var err error
-		buf, err = is.searchMetricNameWithCache(buf[:0], metricID)
-		if err != nil {
-			if err == io.EOF {
-				// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
-				// Skip this metricID for now.
-				continue
-			}
-			return fmt.Errorf("cannot find metricName by metricID %d: %w", metricID, err)
+		var ok bool
+		buf, ok = is.searchMetricNameWithCache(buf[:0], metricID)
+		if !ok {
+			// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
+			// Skip this metricID for now.
+			continue
 		}
 		if err := mn.Unmarshal(buf); err != nil {
-			return fmt.Errorf("cannot unmarshal metricName %q: %w", buf, err)
+			logger.Panicf("FATAL: cannot unmarshal metricName %q: %w", buf, err)
 		}
 		for _, tag := range mn.Tags {
-			_, ok := lns[string(tag.Key)]
-			if !ok {
+			if _, ok := lns[string(tag.Key)]; !ok {
 				foundLabelNames++
 				lns[string(tag.Key)] = struct{}{}
 				if len(lns) >= maxLabelNames {
 					qt.Printf("hit the limit on the number of unique label names: %d", maxLabelNames)
-					return nil
+					return
 				}
 			}
 		}
 	}
 	qt.Printf("get %d distinct label names from %d metricIDs", foundLabelNames, len(metricIDs))
-	return nil
 }
 
 // SearchLabelValuesWithFiltersOnTimeRange returns label values for the given labelName, tfss and tr.
@@ -868,7 +864,8 @@ func (is *indexSearch) searchLabelValuesWithFiltersOnDate(qt *querytracer.Tracer
 		// This would help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
 		metricIDs := filter.AppendTo(nil)
 		qt.Printf("sort %d metricIDs", len(metricIDs))
-		return is.getLabelValuesForMetricIDs(qt, lvs, labelName, metricIDs, maxLabelValues)
+		is.getLabelValuesForMetricIDs(qt, lvs, labelName, metricIDs, maxLabelValues)
+		return nil
 	}
 	if labelName == "__name__" {
 		// __name__ label is encoded as empty string in indexdb.
@@ -927,7 +924,7 @@ func (is *indexSearch) searchLabelValuesWithFiltersOnDate(qt *querytracer.Tracer
 	return nil
 }
 
-func (is *indexSearch) getLabelValuesForMetricIDs(qt *querytracer.Tracer, lvs map[string]struct{}, labelName string, metricIDs []uint64, maxLabelValues int) error {
+func (is *indexSearch) getLabelValuesForMetricIDs(qt *querytracer.Tracer, lvs map[string]struct{}, labelName string, metricIDs []uint64, maxLabelValues int) {
 	if labelName == "" {
 		labelName = "__name__"
 	}
@@ -935,32 +932,27 @@ func (is *indexSearch) getLabelValuesForMetricIDs(qt *querytracer.Tracer, lvs ma
 	foundLabelValues := 0
 	var buf []byte
 	for _, metricID := range metricIDs {
-		var err error
-		buf, err = is.searchMetricNameWithCache(buf[:0], metricID)
-		if err != nil {
-			if err == io.EOF {
-				// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
-				// Skip this metricID for now.
-				continue
-			}
-			return fmt.Errorf("cannot find metricName by metricID %d: %w", metricID, err)
+		var ok bool
+		buf, ok = is.searchMetricNameWithCache(buf[:0], metricID)
+		if !ok {
+			// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
+			// Skip this metricID for now.
+			continue
 		}
 		if err := mn.Unmarshal(buf); err != nil {
-			return fmt.Errorf("cannot unmarshal metricName %q: %w", buf, err)
+			logger.Panicf("FATAL: cannot unmarshal metricName %q: %s", buf, err)
 		}
 		tagValue := mn.GetTagValue(labelName)
-		_, ok := lvs[string(tagValue)]
-		if !ok {
+		if _, ok := lvs[string(tagValue)]; !ok {
 			foundLabelValues++
 			lvs[string(tagValue)] = struct{}{}
 			if len(lvs) >= maxLabelValues {
 				qt.Printf("hit the limit on the number of unique label values for label %q: %d", labelName, maxLabelValues)
-				return nil
+				return
 			}
 		}
 	}
 	qt.Printf("get %d distinct values for label %q from %d metricIDs", foundLabelValues, labelName, len(metricIDs))
-	return nil
 }
 
 // SearchTagValueSuffixes returns all the tag value suffixes for the given tagKey and tagValuePrefix on the given tr.
@@ -1442,38 +1434,35 @@ func (th *topHeap) Pop() interface{} {
 
 // searchMetricNameWithCache appends metric name for the given metricID to dst
 // and returns the result.
-func (db *indexDB) searchMetricNameWithCache(dst []byte, metricID uint64) ([]byte, error) {
+func (db *indexDB) searchMetricNameWithCache(dst []byte, metricID uint64) ([]byte, bool) {
 	metricName := db.getMetricNameFromCache(dst, metricID)
 	if len(metricName) > len(dst) {
-		return metricName, nil
+		return metricName, true
 	}
 
 	is := db.getIndexSearch(noDeadline)
-	var err error
-	dst, err = is.searchMetricName(dst, metricID)
+	var ok bool
+	dst, ok = is.searchMetricName(dst, metricID)
 	db.putIndexSearch(is)
-	if err == nil {
+	if ok {
 		// There is no need in verifying whether the given metricID is deleted,
 		// since the filtering must be performed before calling this func.
 		db.putMetricNameToCache(metricID, dst)
-		return dst, nil
-	}
-	if err != io.EOF {
-		return dst, err
+		return dst, true
 	}
 
 	// Try searching in the external indexDB.
 	if db.doExtDB(func(extDB *indexDB) {
 		is := extDB.getIndexSearch(noDeadline)
-		dst, err = is.searchMetricName(dst, metricID)
+		dst, ok = is.searchMetricName(dst, metricID)
 		extDB.putIndexSearch(is)
-		if err == nil {
+		if ok {
 			// There is no need in verifying whether the given metricID is deleted,
 			// since the filtering must be performed before calling this func.
 			extDB.putMetricNameToCache(metricID, dst)
 		}
-	}) {
-		return dst, err
+	}) && ok {
+		return dst, true
 	}
 
 	// Cannot find MetricName for the given metricID. This may be the case
@@ -1484,7 +1473,7 @@ func (db *indexDB) searchMetricNameWithCache(dst []byte, metricID uint64) ([]byt
 	// Mark the metricID as deleted, so it will be created again when new data point
 	// for the given time series will arrive.
 	db.deleteMetricIDs([]uint64{metricID})
-	return dst, io.EOF
+	return dst, false
 }
 
 // DeleteTSIDs marks as deleted all the TSIDs matching the given tfss.
@@ -1820,36 +1809,36 @@ func (is *indexSearch) getTSIDByMetricNameNoExtDB(dst *TSID, metricName []byte,
 	return false
 }
 
-func (is *indexSearch) searchMetricNameWithCache(dst []byte, metricID uint64) ([]byte, error) {
+func (is *indexSearch) searchMetricNameWithCache(dst []byte, metricID uint64) ([]byte, bool) {
 	metricName := is.db.getMetricNameFromCache(dst, metricID)
 	if len(metricName) > len(dst) {
-		return metricName, nil
+		return metricName, true
 	}
-	var err error
-	dst, err = is.searchMetricName(dst, metricID)
-	if err == nil {
+	var ok bool
+	dst, ok = is.searchMetricName(dst, metricID)
+	if ok {
 		// There is no need in verifying whether the given metricID is deleted,
 		// since the filtering must be performed before calling this func.
 		is.db.putMetricNameToCache(metricID, dst)
-		return dst, nil
+		return dst, true
 	}
-	return dst, err
+	return dst, false
 }
 
-func (is *indexSearch) searchMetricName(dst []byte, metricID uint64) ([]byte, error) {
+func (is *indexSearch) searchMetricName(dst []byte, metricID uint64) ([]byte, bool) {
 	ts := &is.ts
 	kb := &is.kb
 	kb.B = is.marshalCommonPrefix(kb.B[:0], nsPrefixMetricIDToMetricName)
 	kb.B = encoding.MarshalUint64(kb.B, metricID)
 	if err := ts.FirstItemWithPrefix(kb.B); err != nil {
 		if err == io.EOF {
-			return dst, err
+			return dst, false
 		}
-		return dst, fmt.Errorf("error when searching metricName by metricID; searchPrefix %q: %w", kb.B, err)
+		logger.Panicf("FATAL: error when searching metricName by metricID; searchPrefix %q: %w", kb.B, err)
 	}
 	v := ts.Item[len(kb.B):]
 	dst = append(dst, v...)
-	return dst, nil
+	return dst, true
 }
 
 func (is *indexSearch) containsTimeRange(tr TimeRange) (bool, error) {
@@ -1928,18 +1917,15 @@ func (is *indexSearch) updateMetricIDsByMetricNameMatch(qt *querytracer.Tracer,
 				return err
 			}
 		}
-		var err error
-		metricName.B, err = is.searchMetricNameWithCache(metricName.B[:0], metricID)
-		if err != nil {
-			if err == io.EOF {
-				// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
-				// Skip this metricID for now.
-				continue
-			}
-			return fmt.Errorf("cannot find metricName by metricID %d: %w", metricID, err)
+		var ok bool
+		metricName.B, ok = is.searchMetricNameWithCache(metricName.B[:0], metricID)
+		if !ok {
+			// It is likely the metricID->metricName entry didn't propagate to inverted index yet.
+			// Skip this metricID for now.
+			continue
 		}
 		if err := mn.Unmarshal(metricName.B); err != nil {
-			return fmt.Errorf("cannot unmarshal metricName %q: %w", metricName.B, err)
+			logger.Panicf("FATAL: cannot unmarshal metricName %q: %s", metricName.B, err)
 		}
 
 		// Match the mn against tfs.
diff --git a/lib/storage/index_db_test.go b/lib/storage/index_db_test.go
index 28c01b72e..16f5f2dec 100644
--- a/lib/storage/index_db_test.go
+++ b/lib/storage/index_db_test.go
@@ -3,7 +3,6 @@ package storage
 import (
 	"bytes"
 	"fmt"
-	"io"
 	"math/rand"
 	"os"
 	"reflect"
@@ -655,19 +654,19 @@ func testIndexDBCheckTSIDByName(db *indexDB, mns []MetricName, tsids []TSID, isC
 		}
 
 		// Search for metric name for the given metricID.
-		var err error
-		metricNameCopy, err = db.searchMetricNameWithCache(metricNameCopy[:0], genTSID.TSID.MetricID)
-		if err != nil {
-			return fmt.Errorf("error in searchMetricNameWithCache for metricID=%d; i=%d: %w", genTSID.TSID.MetricID, i, err)
+		var ok bool
+		metricNameCopy, ok = db.searchMetricNameWithCache(metricNameCopy[:0], genTSID.TSID.MetricID)
+		if !ok {
+			return fmt.Errorf("cannot find metricName for metricID=%d; i=%d", genTSID.TSID.MetricID, i)
 		}
 		if !bytes.Equal(metricName, metricNameCopy) {
 			return fmt.Errorf("unexpected mn for metricID=%d;\ngot\n%q\nwant\n%q", genTSID.TSID.MetricID, metricNameCopy, metricName)
 		}
 
 		// Try searching metric name for non-existent MetricID.
-		buf, err := db.searchMetricNameWithCache(nil, 1)
-		if err != io.EOF {
-			return fmt.Errorf("expecting io.EOF error when searching for non-existing metricID; got %v", err)
+		buf, found := db.searchMetricNameWithCache(nil, 1)
+		if found {
+			return fmt.Errorf("unexpected metricName found for non-existing metricID; got %X", buf)
 		}
 		if len(buf) > 0 {
 			return fmt.Errorf("expecting empty buf when searching for non-existent metricID; got %X", buf)
diff --git a/lib/storage/partition.go b/lib/storage/partition.go
index c81b05a77..92073f26b 100644
--- a/lib/storage/partition.go
+++ b/lib/storage/partition.go
@@ -1779,6 +1779,18 @@ func mustOpenParts(path string, partNames []string) []*partWrapper {
 	des := fs.MustReadDir(path)
 	m := make(map[string]struct{}, len(partNames))
 	for _, partName := range partNames {
+		// Make sure the partName exists on disk.
+		// If it is missing, then manual action from the user is needed,
+		// since this is unexpected state, which cannot occur under normal operation,
+		// including unclean shutdown.
+		partPath := filepath.Join(path, partName)
+		if !fs.IsPathExist(partPath) {
+			partsFile := filepath.Join(path, partsFilename)
+			logger.Panicf("FATAL: part %q is listed in %q, but is missing on disk; "+
+				"ensure %q contents is not corrupted; remove %q to rebuild its' content from the list of existing parts",
+				partPath, partsFile, partsFile, partsFile)
+		}
+
 		m[partName] = struct{}{}
 	}
 	for _, de := range des {
diff --git a/lib/storage/search.go b/lib/storage/search.go
index 1873939f5..f5b4ab7f8 100644
--- a/lib/storage/search.go
+++ b/lib/storage/search.go
@@ -211,16 +211,12 @@ func (s *Search) NextMetricBlock() bool {
 				// Skip the block, since it contains only data outside the configured retention.
 				continue
 			}
-			var err error
-			s.MetricBlockRef.MetricName, err = s.idb.searchMetricNameWithCache(s.MetricBlockRef.MetricName[:0], tsid.MetricID)
-			if err != nil {
-				if err == io.EOF {
-					// Skip missing metricName for tsid.MetricID.
-					// It should be automatically fixed. See indexDB.searchMetricNameWithCache for details.
-					continue
-				}
-				s.err = err
-				return false
+			var ok bool
+			s.MetricBlockRef.MetricName, ok = s.idb.searchMetricNameWithCache(s.MetricBlockRef.MetricName[:0], tsid.MetricID)
+			if !ok {
+				// Skip missing metricName for tsid.MetricID.
+				// It should be automatically fixed. See indexDB.searchMetricNameWithCache for details.
+				continue
 			}
 			s.prevMetricID = tsid.MetricID
 		}
diff --git a/lib/storage/storage.go b/lib/storage/storage.go
index fff06b435..7d88d36c5 100644
--- a/lib/storage/storage.go
+++ b/lib/storage/storage.go
@@ -1114,15 +1114,12 @@ func (s *Storage) SearchMetricNames(qt *querytracer.Tracer, tfss []*TagFilters,
 				return nil, err
 			}
 		}
-		var err error
-		metricName, err = idb.searchMetricNameWithCache(metricName[:0], metricID)
-		if err != nil {
-			if err == io.EOF {
-				// Skip missing metricName for metricID.
-				// It should be automatically fixed. See indexDB.searchMetricName for details.
-				continue
-			}
-			return nil, fmt.Errorf("error when searching metricName for metricID=%d: %w", metricID, err)
+		var ok bool
+		metricName, ok = idb.searchMetricNameWithCache(metricName[:0], metricID)
+		if !ok {
+			// Skip missing metricName for metricID.
+			// It should be automatically fixed. See indexDB.searchMetricName for details.
+			continue
 		}
 		if _, ok := metricNamesSeen[string(metricName)]; ok {
 			// The given metric name was already seen; skip it
@@ -1175,13 +1172,11 @@ func (s *Storage) prefetchMetricNames(qt *querytracer.Tracer, srcMetricIDs []uin
 				return err
 			}
 		}
-		metricName, err = is.searchMetricNameWithCache(metricName[:0], metricID)
-		if err != nil {
-			if err == io.EOF {
-				missingMetricIDs = append(missingMetricIDs, metricID)
-				continue
-			}
-			return fmt.Errorf("error in pre-fetching metricName for metricID=%d: %w", metricID, err)
+		var ok bool
+		metricName, ok = is.searchMetricNameWithCache(metricName[:0], metricID)
+		if !ok {
+			missingMetricIDs = append(missingMetricIDs, metricID)
+			continue
 		}
 	}
 	idb.doExtDB(func(extDB *indexDB) {
@@ -1193,11 +1188,7 @@ func (s *Storage) prefetchMetricNames(qt *querytracer.Tracer, srcMetricIDs []uin
 					return
 				}
 			}
-			metricName, err = is.searchMetricNameWithCache(metricName[:0], metricID)
-			if err != nil && err != io.EOF {
-				err = fmt.Errorf("error in pre-fetching metricName for metricID=%d in extDB: %w", metricID, err)
-				return
-			}
+			metricName, _ = is.searchMetricNameWithCache(metricName[:0], metricID)
 		}
 	})
 	if err != nil && err != io.EOF {