Server Configuration

Many Seq options can be configured through the Settings section of the web user interface. Lower-level settings, especially those that control the HTTP endpoint, or require a restart to be applied, are stored in the Seq.json configuration file, and manipulated using the seq config command-line. Stop Seq before changing these settings.

The seq config command-line

From an administrative command prompt on the Seq server, running seq config list will list the available settings and their values:

seq config list

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Docker syntax

The seq config commands can be invoked on the Docker container:

docker run --rm -it -v <volume> datalust/seq config list

or, within init scripts via seqsvr, e.g. seqsvr config list.

Setting values can be changed with seq config set by specifying the setting name and value:

seq config set -k api.listenUris -v https://example.com,https://example.com:45341
seq config clear -k storage.queryParallelism
seq service restart

Settings that accept multiple values can be specified by listing values separated by a comma ,.

Values can be reset to their defaults using seq config clear and the setting name. The details of these commands are listed in the Server Command Line documentation.

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Seq reads settings Seq.json at startup, so the Seq service must be restarted for changes to take effect.

Environment variable overrides

Each setting value can be overridden at runtime by specifying an environment variable of the form SEQ_<setting path>, where <setting path> contains one element for each dotted segment of the setting name, separated by underscores.

For example the setting api.listenUris can overridden with the SEQ_API_LISTENURIS variable.

Secret Store overrides

Some setting values, for example, certificates.defaultPassword, metastore.postgres.connectionString, or metastore.msSql.connectionString, should not be stored in plain text.

Seq provides the secret set command as an alternative to config set for this purpose:

echo p@ssw0rd | seq secret set -k certificates.defaultPassword --value-stdin

The --value-stdin parameter avoids leaving sensitive information in the shell command history, or exposing it to other privileged processes via the seq process's command-line.

The secret set command encrypts values using the secret key and stores them in Secrets/. Secret Store values are applied last, so they will override values in Seq.json as well as any values supplied in environment variables.

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In Docker

To load values into the secret store under Docker, call seqsrv secret set from an init script. The script can pull the secret value from an external store, or read it from a file alongside the script which the script can delete after reading.

Settings

Settings can be viewed and updated from the command-line using the seq config commands. Settings also support overrides in environment variables and the secret store. The matching environment variable name for each setting is shown in the detailed documentation below.

api.canonicalUri

The address that the server can be accessed on externally. If specified, Seq will assume that all requests are served under this URL, all inbound links and redirects Seq generates will be based on this URL.

The value can be overridden using the SEQ_API_CANONICALURI environment variable.

api.corsAllowedOrigins

Origins from which the full API will be accessible using CORS. Note that this is not necessary for ingestion - events can always be sent to the ingestion endpoint using CORS.

The value can be overridden using the SEQ_API_CORSALLOWEDORIGINS environment variable.

api.frameAncestors

Value of the content security policy frame-ancestors directive. Comma-delimited list of hosts that are allowed to embed the Seq UI within an iframe.

The value can be overridden using the SEQ_API_FRAMEANCESTORS environment variable.

api.globalQueueLimit

The maximum number of waiting API requests to queue. This setting has no effect unless GlobalRateLimit is also set.

The value can be overridden using the SEQ_API_GLOBALQUEUELIMIT environment variable.

api.globalRateLimit

The maximum number of concurrent API requests to allow

The value can be overridden using the SEQ_API_GLOBALRATELIMIT environment variable.

api.hardSessionExpirySeconds

If non-null, this will override the various session expiry timeouts used by the different authentication providers. The initial value is null (no additional hard session expiry override).

The value can be overridden using the SEQ_API_HARDSESSIONEXPIRYSECONDS environment variable.

api.hstsIncludeSubDomains

The includeSubdomains field set in the HSTS header, if enabled.

The value can be overridden using the SEQ_API_HSTSINCLUDESUBDOMAINS environment variable.

api.hstsMaxAge

The max-age specified in the HSTS header in seconds, if enabled. The initial value is 31536000 (365 days).

The value can be overridden using the SEQ_API_HSTSMAXAGE environment variable.

api.idleSessionExpirySeconds

If non-null, this will set an expiry timeout that will revoke user sessions after a period of inactivity. The initial value is 172800 (48 hours).

The value can be overridden using the SEQ_API_IDLESESSIONEXPIRYSECONDS environment variable.

api.ingestionPort

Maintained for compatibility reasons. New configurations should use api.ingestionPorts.

The value can be overridden using the SEQ_API_INGESTIONPORT environment variable.

api.ingestionPorts

The ports that the server will limit to event ingestion.Note that corresponding entries (with the same ports) must also exist in api.listenUris.

The value can be overridden using the SEQ_API_INGESTIONPORTS environment variable.

api.ingestQueueLimit

The maximum number of waiting ingestion requests to queue. This setting has no effect unless IngestRateLimit is also set.

The value can be overridden using the SEQ_API_INGESTQUEUELIMIT environment variable.

api.ingestRateLimit

The maximum number of concurrent ingestion requests to allow

The value can be overridden using the SEQ_API_INGESTRATELIMIT environment variable.

api.integratedAuthenticationScheme

Windows: The authentication scheme used for Windows authentication. IntegratedWindowsAuthentication (the default) and Negotiate are supported.

The value can be overridden using the SEQ_API_INTEGRATEDAUTHENTICATIONSCHEME environment variable.

api.listenUris

The addresses that the server will listen on. The first entry listed will be used as the default when generating URIs for apps and notifications unless overriden by api.canonicalUri.

The value can be overridden using the SEQ_API_LISTENURIS environment variable.

api.minRequestBodyDataRateBytesPerSecond

The minimum request body data rate in bytes/second. The default is 240 bytes/second. Clear this setting todisable the limit entirely. Not supported when using HTTP.sys on Windows.

The value can be overridden using the SEQ_API_MINREQUESTBODYDATARATEBYTESPERSECOND environment variable.

api.minRequestBodyDataRateGracePeriodMilliseconds

The time limit within which the client must increase its request body data rate up to the minimum. The default is 5000 (5 seconds). Not supported when using HTTP.sys on Windows.

The value can be overridden using the SEQ_API_MINREQUESTBODYDATARATEGRACEPERIODMILLISECONDS environment variable.

api.queryQueueLimit

The maximum number of waiting query requests to queue. This setting has no effect unless QueryRateLimit is also set.

The value can be overridden using the SEQ_API_QUERYQUEUELIMIT environment variable.

api.queryRateLimit

The maximum number of concurrent query requests to allow

The value can be overridden using the SEQ_API_QUERYRATELIMIT environment variable.

api.redirectHttpToHttps

Whether to redirect HTTP requests to the first HTTPS endpoint listed in api.listenUris. If set to True, the HSTS header will also be set.

The value can be overridden using the SEQ_API_REDIRECTHTTPTOHTTPS environment variable.

api.webServer

Windows: The web server that will host the API. Allowed values are HttpSys (HTTP.sys, the default) and Kestrel. OpenTelemetry ingestion requires Kestrel for gRPC support. Integrated Windows Authentication requires HttpSys.

Supported values are:

• HttpSys - The Windows HTTP.sys web server.
• Kestrel - The Kestrel web server.

The value can be overridden using the SEQ_API_WEBSERVER environment variable.

appHost.executionPolicy

Control whether installed Seq Apps packages can be executed. This setting is provided as an additional defensive security measure for high-sensitivity environments. The default is to allow installed apps to be executed.

Supported values are:

• AllowAll - Allow execution of installed apps.
• Disallow - Disallow execution of installed apps.

The value can be overridden using the SEQ_APPHOST_EXECUTIONPOLICY environment variable.

appHost.installPolicy

Control whether Seq App packages can be installed from configured feeds. This setting is provided as an additional defensive security measure for high-sensitivity environments. The default is to allow new packages to be installed.

Supported values are:

• AllowAll - Allow installation of new app packages.
• Disallow - Disallow the installation of any new app packages.

The value can be overridden using the SEQ_APPHOST_INSTALLPOLICY environment variable.

audit.auditPath

The fully-qualified local path where Seq should write audit files. Filenames have the form seq-audit-YYYYMMDD-SESSION.ndjson, where YYYYMMDD is the file creation year, month, and day (UTC), and SESSION is the unique audit session identifier.

The value can be overridden using the SEQ_AUDIT_AUDITPATH environment variable.

audit.auditServerApiKey

API key for the audit server. Should be supplied if AuditServerUrl is configured.

The value can be overridden using the SEQ_AUDIT_AUDITSERVERAPIKEY environment variable.

audit.auditServerUrl

The address of a second Seq instance to receive audit logs. The URL should use the https scheme.

The value can be overridden using the SEQ_AUDIT_AUDITSERVERURL environment variable.

certificates.certificatesPath

Optionally, a folder to search for certificate files; if not specified, Certificates/ under thestorage root will be used.

The value can be overridden using the SEQ_CERTIFICATES_CERTIFICATESPATH environment variable.

certificates.defaultPassword

The default password used when decrypting encoded certificate bundles (.pfx files).

The value can be overridden using the SEQ_CERTIFICATES_DEFAULTPASSWORD environment variable.

diagnostics.internalLoggingLevel

Seq's own internal logging level. Modifying this value may cause significantly higher I/O load and is not recommended. The default is Information.

The value can be overridden using the SEQ_DIAGNOSTICS_INTERNALLOGGINGLEVEL environment variable.

diagnostics.internalLogPath

The location for Seq's own internal log files.

The value can be overridden using the SEQ_DIAGNOSTICS_INTERNALLOGPATH environment variable.

diagnostics.internalLogServerApiKey

API key for the internal log server.

The value can be overridden using the SEQ_DIAGNOSTICS_INTERNALLOGSERVERAPIKEY environment variable.

diagnostics.internalLogServerUrl

Send Seq's internal logs to another Seq server.

The value can be overridden using the SEQ_DIAGNOSTICS_INTERNALLOGSERVERURL environment variable.

diagnostics.metricsSamplingIntervalSeconds

Interval (seconds) at which Seq will write metrics information to its internal log file.

The value can be overridden using the SEQ_DIAGNOSTICS_METRICSSAMPLINGINTERVALSECONDS environment variable.

diagnostics.nativeStorageMetricsSamplingIntervalMinutes

Interval (minutes) at which Seq will write native storage metrics to its internal log file.

The value can be overridden using the SEQ_DIAGNOSTICS_NATIVESTORAGEMETRICSSAMPLINGINTERVALMINUTES environment variable.

diagnostics.telemetryServerUrl

Send Seq's error telemetry (if enabled) to another Seq server.

The value can be overridden using the SEQ_DIAGNOSTICS_TELEMETRYSERVERURL environment variable.

features.enabled

The non-default features enabled on the Seq instance.

The value can be overridden using the SEQ_FEATURES_ENABLED environment variable.

firstRun.adminPasswordHash

A salted, cryptographically-hashed, Base64-encoded default password for the administrator account, ignored after the first time Seq is run. Use seq config hash to compute a value that can be stored in this setting. Alternatively, consider using the --default-admin-password-stdin argument to the seq run command. The default when no password is supplied is to not enable authentication.

The value can be overridden using the SEQ_FIRSTRUN_ADMINPASSWORDHASH environment variable.

firstRun.adminUsername

A default username for the administrator account, ignored after the first time Seq is run. The default is admin.

The value can be overridden using the SEQ_FIRSTRUN_ADMINUSERNAME environment variable.

firstRun.requireAuthenticationForHttpIngestion

If true, API keys or user authentication will be required for HTTP/S ingestion; ignored after thefirst time Seq is run.

The value can be overridden using the SEQ_FIRSTRUN_REQUIREAUTHENTICATIONFORHTTPINGESTION environment variable.

metastore.msSql.connectionString

A connection string for the Microsoft SQL Server/Azure SQL instance into which metadata will be stored. If null,local metadata storage will be used. The default is null.

The value can be overridden using the SEQ_METASTORE_MSSQL_CONNECTIONSTRING environment variable.

metastore.msSql.msiResource

If the connection must use an Azure Managed Service Identity, the resource for which to request an access token; normally this will be https://database.windows.net/; the default is to not use an Azure MSI.

The value can be overridden using the SEQ_METASTORE_MSSQL_MSIRESOURCE environment variable.

metastore.msSql.msiTenantId

If using an Azure Managed Service Identity and the identity has access to multiple tenants, the tenant id; the default is to not specify a tenant id.

The value can be overridden using the SEQ_METASTORE_MSSQL_MSITENANTID environment variable.

metastore.msSql.schema

The name of the schema under which Seq should store metadata. The default is dbo.

The value can be overridden using the SEQ_METASTORE_MSSQL_SCHEMA environment variable.

metastore.postgres.connectionString

A connection string for the PostgreSQL instance into which metadata will be stored. If null,local metadata storage will be used. The default is null.

The value can be overridden using the SEQ_METASTORE_POSTGRES_CONNECTIONSTRING environment variable.

metastore.postgres.schema

The name of the schema under which Seq should store metadata. The default is seq.

The value can be overridden using the SEQ_METASTORE_POSTGRES_SCHEMA environment variable.

process.workingSetLimitBytes

Windows: the maximum working set that may be consumed by the Seq process, in bytes. The default is no limit.

The value can be overridden using the SEQ_PROCESS_WORKINGSETLIMITBYTES environment variable.

runtime.expressionNestingLimit

The nesting limit applied to expressions in queries and filters. Higher values may allow very complex queries to cause server crashes. The default is platform-dependent.

The value can be overridden using the SEQ_RUNTIME_EXPRESSIONNESTINGLIMIT environment variable.

runtime.nativeExpressionNestingLimit

The nesting limit applied to expressions in queries and filters executed in the underlying event storage engine. Higher values may allow very complex queries to cause server crashes. The default is based on runtime.expressionNestingLimit (SEQ_RUNTIME_EXPRESSIONNESTINGLIMIT).

The value can be overridden using the SEQ_RUNTIME_NATIVEEXPRESSIONNESTINGLIMIT environment variable.

secretKey.provider

An executable that will write the Base64-encoded secret key to STDOUT when invoked. If specified, this will override the secret key found in Seq.json or any environment variables.

The value can be overridden using the SEQ_SECRETKEY_PROVIDER environment variable.

secretKey.providerArgs

Command-line arguments to pass to the secret key provider executable, if configured.

The value can be overridden using the SEQ_SECRETKEY_PROVIDERARGS environment variable.

services.servicesBaseUri

The base URL Seq uses for service discovery, if enabled. The default is https://datalust.co.

The value can be overridden using the SEQ_SERVICES_SERVICESBASEURI environment variable.

storage.disableFreeDiskSpaceChecking

Disable free disk space checking for filesystems where it may be very inefficient or unnecessary. If checking is disabled Seq can't protect from running out of disk space.

The value can be overridden using the SEQ_STORAGE_DISABLEFREEDISKSPACECHECKING environment variable.

storage.flare.concurrentReaderLimit

The maximum number of read queries that can concurrently execute within the storage engine. Increasing this value can improve throughput, at the expense of additional risk of stampedes causingservice instability. The default is 5.

The value can be overridden using the SEQ_STORAGE_FLARE_CONCURRENTREADERLIMIT environment variable.

storage.flare.indexerPriority

The priority assigned to storage management and indexing; the default value 0 will cause all required management tasks to proceed normally. Higher values represent the fraction of maintenance time during which these tasks should yield.

The value can be overridden using the SEQ_STORAGE_FLARE_INDEXERPRIORITY environment variable.

storage.flare.readerParallelismLimit

The maximum number of storage engine threads to create for each parallel query. The default is calculated from available system resources.

The value can be overridden using the SEQ_STORAGE_FLARE_READERPARALLELISMLIMIT environment variable.

storage.maximumFutureTimestampDriftSeconds

The future time difference allowed between the server clock and incoming event timestamps, before server timestamps will be used. This setting prevents performance and usability problems associated with far-future event timestamps. Past timestamps are always accepted as-is. The default is 3420 (57 minutes); clear this setting to accept all future timestamps.

The value can be overridden using the SEQ_STORAGE_MAXIMUMFUTURETIMESTAMPDRIFTSECONDS environment variable.

storage.secretKey

The encryption key used to protect secrets and sensitive values in the Seq metadata store.

Windows: this value is itself encrypted and must be retrieved using the seq show-key command for secure backup.

Linux/macOS: this value is stored unencrypted in Seq.json; use the SEQ_STORAGE_SECRETKEY variable for improved confidentiality, or configure secretKey.provider.

The value can be overridden using the SEQ_STORAGE_SECRETKEY environment variable.

Seq.json Example

An example Seq.json configuration file is shown below.

{
  "api": {
    "ingestionPorts": [
      45341
    ],
    "canonicalUri": null,
    "corsAllowedOrigins": [],
    "frameAncestors": [],
    "hardSessionExpirySeconds": null,
    "hstsIncludeSubDomains": false,
    "hstsMaxAge": 31536000,
    "idleSessionExpirySeconds": 172800,
    "ingestionPort": null,
    "integratedAuthenticationScheme": null,
    "listenUris": [
      "https://seq.example.com",
      "https://seq.example.com:45341"
    ],
    "redirectHttpToHttps": false,
    "minRequestBodyDataRateBytesPerSecond": 240.0,
    "minRequestBodyDataRateGracePeriodMilliseconds": 5000,
    "webServer": null,
    "globalRateLimit": null,
    "globalQueueLimit": null,
    "ingestRateLimit": null,
    "ingestQueueLimit": null,
    "queryRateLimit": null,
    "queryQueueLimit": null
  },
  "appHost": {
    "installPolicy": null,
    "executionPolicy": null
  },
  "audit": {
    "auditServerUrl": null,
    "auditServerApiKey": null,
    "auditPath": null
  },
  "certificates": {
    "certificatesPath": null,
    "defaultPassword": null
  },
  "diagnostics": {
    "internalLogPath": null,
    "internalLoggingLevel": "Information",
    "internalLogServerApiKey": null,
    "internalLogServerUrl": null,
    "metricsSamplingIntervalSeconds": 300,
    "nativeStorageMetricsSamplingIntervalMinutes": 60,
    "telemetryServerUrl": null
  },
  "features": {
    "enabled": []
  },
  "firstRun": {
    "adminPasswordHash": null,
    "adminUsername": null,
    "requireAuthenticationForHttpIngestion": false
  },
  "metastore": {
    "msSql": {
      "connectionString": null,
      "msiResource": null,
      "msiTenantId": null,
      "schema": null
    },
    "postgres": {
      "connectionString": null,
      "schema": null
    }
  },
  "process": {
    "workingSetLimitBytes": null
  },
  "runtime": {
    "expressionNestingLimit": null,
    "nativeExpressionNestingLimit": null
  },
  "secretKey": {
    "provider": null,
    "providerArgs": null
  },
  "services": {
    "servicesBaseUri": null
  },
  "storage": {
    "secretKey": "pmk.4S7Fk7P6yU6IthKk/rXETA==",
    "flare": {
      "concurrentReaderLimit": null,
      "readerParallelismLimit": null,
      "indexerPriority": 0.0
    },
    "disableFreeDiskSpaceChecking": false,
    "maximumFutureTimestampDriftSeconds": 3420
  }
}