It is safe upgrading VictoriaLogs to new versions unless [release notes](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) say otherwise.
It is safe skipping multiple versions during the upgrade unless [release notes](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) say otherwise.
It is recommended performing regular upgrades to the latest version, since it may contain important bug fixes, performance optimizations or new features.
It is also safe downgrading to older versions unless [release notes](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) say otherwise.
The following steps must be performed during the upgrade / downgrade procedure:
* Send `SIGINT` signal to VictoriaLogs process in order to gracefully stop it.
See [how to send signals to processes](https://stackoverflow.com/questions/33239959/send-signal-to-process-from-command-line).
* Wait until the process stops. This can take a few seconds.
By default VictoriaLogs stores log entries with timestamps in the time range `[now-7d, now]`, while dropping logs outside the given time range.
E.g. it uses the retention of 7 days. The retention can be configured with `-retentionPeriod` command-line flag.
This flag accepts values starting from `1d` (one day) up to `100y` (100 years). See [these docs](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-durations)
for the supported duration formats.
For example, the following command starts VictoriaLogs with the retention of 8 weeks:
The `vl_rows_dropped_total` [metric](#monitoring) is incremented each time an ingested log entry is dropped because of timestamp outside the retention.
VictoriaLogs stores all its data in a single directory - `victoria-logs-data`. The path to the directory can be changed via `-storageDataPath` command-line flag.
For example, the following command starts VictoriaLogs, which stores the data at `/var/lib/victoria-logs`:
VictoriaLogs supports multitenancy. A tenant is identified by `(AccountID, ProjectID)` pair, where `AccountID` and `ProjectID` are arbitrary 32-bit unsigned integeres.
The `AccountID` and `ProjectID` fields can be set during [data ingestion](https://docs.victoriametrics.com/VictoriaLogs/data-ingestion/)
and [querying](https://docs.victoriametrics.com/VictoriaLogs/querying/) via `AccountID` and `ProjectID` request headers.
If `AccountID` and/or `ProjectID` request headers aren't set, then the default `0` value is used.
VictoriaLogs has very low overhead for per-tenant management, so it is OK to have thousands of tenants in a single VictoriaLogs instance.
VictoriaLogs doesn't perform per-tenant authorization. Use [vmauth](https://docs.victoriametrics.com/vmauth.html) or similar tools for per-tenant authorization.
Here is a [benchmark suite](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/deployment/logs-benchmark) for comparing data ingestion performance
and resource usage between VictoriaLogs and Elasticsearch.
Pass `-help` to VictoriaLogs in order to see the list of supported command-line flags with their description:
```
-cacheExpireDuration duration
Items are removed from in-memory caches after they aren't accessed for this duration. Lower values may reduce memory usage at the cost of higher CPU usage. See also -prevCacheRemovalPercent (default 30m0s)
-enableTCP6
Whether to enable IPv6 for listening and dialing. By default, only IPv4 TCP and UDP is used
-envflag.enable
Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
-envflag.prefix string
Prefix for environment variables if -envflag.enable is set
-flagsAuthKey string
Auth key for /flags endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
-fs.disableMmap
Whether to use pread() instead of mmap() for reading data files. By default, mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
-futureRetention value
Log entries with timestamps bigger than now+futureRetention are rejected during data ingestion; see https://docs.victoriametrics.com/VictoriaLogs/#retention
The following optional suffixes are supported: h (hour), d (day), w (week), y (year). If suffix isn't set, then the duration is counted in months (default 2d)
-gogc int
GOGC to use. See https://tip.golang.org/doc/gc-guide (default 100)
-http.connTimeout duration
Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
-http.disableResponseCompression
Disable compression of HTTP responses to save CPU resources. By default, compression is enabled to save network bandwidth
-http.idleConnTimeout duration
Timeout for incoming idle http connections (default 1m0s)
-http.maxGracefulShutdownDuration duration
The maximum duration for a graceful shutdown of the HTTP server. A highly loaded server may require increased value for a graceful shutdown (default 7s)
-http.pathPrefix string
An optional prefix to add to all the paths handled by http server. For example, if '-http.pathPrefix=/foo/bar' is set, then all the http requests will be handled on '/foo/bar/*' paths. This may be useful for proxied requests. See https://www.robustperception.io/using-external-urls-and-proxies-with-prometheus
-http.shutdownDelay duration
Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
-httpAuth.password string
Password for HTTP Basic Auth. The authentication is disabled if -httpAuth.username is empty
-httpAuth.username string
Username for HTTP Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
-httpListenAddr string
TCP address to listen for http connections. See also -httpListenAddr.useProxyProtocol (default ":9428")
-httpListenAddr.useProxyProtocol
Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing
-inmemoryDataFlushInterval duration
The interval for guaranteed saving of in-memory data to disk. The saved data survives unclean shutdown such as OOM crash, hardware reset, SIGKILL, etc. Bigger intervals may help increasing lifetime of flash storage with limited write cycles (e.g. Raspberry PI). Smaller intervals increase disk IO load. Minimum supported value is 1s (default 5s)
-insert.maxLineSizeBytes size
The maximum size of a single line, which can be read by /insert/* handlers
Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 262144)
-insert.maxQueueDuration duration
The maximum duration to wait in the queue when -maxConcurrentInserts concurrent insert requests are executed (default 1m0s)
-internStringCacheExpireDuration duration
The expiry duration for caches for interned strings. See https://en.wikipedia.org/wiki/String_interning . See also -internStringMaxLen and -internStringDisableCache (default 6m0s)
-internStringDisableCache
Whether to disable caches for interned strings. This may reduce memory usage at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringCacheExpireDuration and -internStringMaxLen
-internStringMaxLen int
The maximum length for strings to intern. Lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringDisableCache and -internStringCacheExpireDuration (default 500)
-logIngestedRows
Whether to log all the ingested log entries; this can be useful for debugging of data ingestion; see https://docs.victoriametrics.com/VictoriaLogs/data-ingestion/ ; see also -logNewStreams
-logNewStreams
Whether to log creation of new streams; this can be useful for debugging of high cardinality issues with log streams; see https://docs.victoriametrics.com/VictoriaLogs/keyConcepts.html#stream-fields ; see also -logIngestedRows
-loggerDisableTimestamps
Whether to disable writing timestamps in logs
-loggerErrorsPerSecondLimit int
Per-second limit on the number of ERROR messages. If more than the given number of errors are emitted per second, the remaining errors are suppressed. Zero values disable the rate limit
-loggerFormat string
Format for logs. Possible values: default, json (default "default")
-loggerJSONFields string
Allows renaming fields in JSON formatted logs. Example: "ts:timestamp,msg:message" renames "ts" to "timestamp" and "msg" to "message". Supported fields: ts, level, caller, msg
-loggerLevel string
Minimum level of errors to log. Possible values: INFO, WARN, ERROR, FATAL, PANIC (default "INFO")
-loggerOutput string
Output for the logs. Supported values: stderr, stdout (default "stderr")
-loggerTimezone string
Timezone to use for timestamps in logs. Timezone must be a valid IANA Time Zone. For example: America/New_York, Europe/Berlin, Etc/GMT+3 or Local (default "UTC")
-loggerWarnsPerSecondLimit int
Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
-maxConcurrentInserts int
The maximum number of concurrent insert requests. Default value should work for most cases, since it minimizes the memory usage. The default value can be increased when clients send data over slow networks. See also -insert.maxQueueDuration (default 12)
-memory.allowedBytes size
Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
-memory.allowedPercent float
Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
-metricsAuthKey string
Auth key for /metrics endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
-pprofAuthKey string
Auth key for /debug/pprof/* endpoints. It must be passed via authKey query arg. It overrides httpAuth.* settings
-prevCacheRemovalPercent float
Items in the previous caches are removed when the percent of requests it serves becomes lower than this value. Higher values reduce memory usage at the cost of higher CPU usage. See also -cacheExpireDuration (default 0.1)
-pushmetrics.extraLabel array
Optional labels to add to metrics pushed to -pushmetrics.url . For example, -pushmetrics.extraLabel='instance="foo"' adds instance="foo" label to all the metrics pushed to -pushmetrics.url
Supports an array of values separated by comma or specified via multiple flags.
-pushmetrics.interval duration
Interval for pushing metrics to -pushmetrics.url (default 10s)
-pushmetrics.url array
Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default, metrics exposed at /metrics page aren't pushed to any remote storage
Supports an array of values separated by comma or specified via multiple flags.
-retentionPeriod value
Log entries with timestamps older than now-retentionPeriod are automatically deleted; log entries with timestamps outside the retention are also rejected during data ingestion; the minimum supported retention is 1d (one day); see https://docs.victoriametrics.com/VictoriaLogs/#retention
The following optional suffixes are supported: h (hour), d (day), w (week), y (year). If suffix isn't set, then the duration is counted in months (default 7d)
-search.maxConcurrentRequests int
The maximum number of concurrent search requests. It shouldn't be high, since a single request can saturate all the CPU cores, while many concurrently executed requests may require high amounts of memory. See also -search.maxQueueDuration (default 6)
-search.maxQueryDuration duration
The maximum duration for query execution (default 30s)
-search.maxQueueDuration duration
The maximum time the search request waits for execution when -search.maxConcurrentRequests limit is reached; see also -search.maxQueryDuration (default 10s)
-select.maxSortBufferSize size
Query results from /select/logsql/query are automatically sorted by _time if their summary size doesn't exceed this value; otherwise query results are streamed in the response without sorting; too big value for this flag may result in high memory usage, since the sorting is performed in memory
Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 1048576)
-storageDataPath string
Path to directory with the VictoriaLogs data; see https://docs.victoriametrics.com/VictoriaLogs/#storage (default "victoria-logs-data")
-tls
Whether to enable TLS for incoming HTTP requests at -httpListenAddr (aka https). -tlsCertFile and -tlsKeyFile must be set if -tls is set
-tlsCertFile string
Path to file with TLS certificate if -tls is set. Prefer ECDSA certs instead of RSA certs as RSA certs are slower. The provided certificate file is automatically re-read every second, so it can be dynamically updated
-tlsCipherSuites array
Optional list of TLS cipher suites for incoming requests over HTTPS if -tls is set. See the list of supported cipher suites at https://pkg.go.dev/crypto/tls#pkg-constants
Supports an array of values separated by comma or specified via multiple flags.
-tlsKeyFile string
Path to file with TLS key if -tls is set. The provided key file is automatically re-read every second, so it can be dynamically updated
-tlsMinVersion string
Optional minimum TLS version to use for incoming requests over HTTPS if -tls is set. Supported values: TLS10, TLS11, TLS12, TLS13
