> For the complete documentation index, see [llms.txt](https://metalbear.com/mirrord/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://metalbear.com/mirrord/docs/sharing-the-cluster/db-branching/redis.md). # Redis This page covers DB branching for Redis. For the general concepts, the full list of config fields, and how a session behaves, see the [DB Branching overview](/mirrord/docs/sharing-the-cluster/db-branching.md). Redis is the only engine that supports both branch locations: * `"location": "remote"` (default) provisions a branch pod in the cluster, like the other engines. * `"location": "local"` spawns a Redis instance on your own machine. {% hint style="info" %} Remote Redis branching requires operator `3.168.0`, mirrord CLI `3.217.0`, and operator Helm chart `3.168.0` with the `operator.redisBranching` value set to `true`. Local Redis branching only requires mirrord CLI `3.180.0` - there are no operator or chart version requirements, since a local branch runs entirely on your machine. {% endhint %} ### Remote Branches ```json { "feature": { "db_branches": [ { "id": "cache-redis", "type": "redis", "version": "7.2", "name": "0", "connection": { "url": "REDIS_URL" }, "copy": { "mode": "empty" } } ] } } ``` The `connection` field describes how mirrord locates the source Redis connection details - a full connection URL or individual parameters (host, port, user, password, database). See [Connection Modes](/mirrord/docs/sharing-the-cluster/db-branching/more/connection.md) for all supported sources, including Kubernetes Secrets, Google Secret Manager, literal values, and composite environment variables. #### Database Index For Redis, the `name` field is the database **index** Redis uses to select a logical database rather than a name, so it must be a valid non-negative number. If omitted, it defaults to index `0`. ### Copy Modes Redis copy modes apply only to **remote** Redis branches. A local Redis branch always starts empty. Redis supports two modes: | Mode | What gets cloned | | ------------------- | ------------------------------------------------------------------------ | | `"empty"` (default) | Nothing - a fresh, empty Redis instance | | `"all"` | Keys from the source Redis instance, optionally filtered with `patterns` | By default `"all"` copies the entire keyspace. To copy only a subset, add `patterns` - a list of [`SCAN MATCH`](https://redis.io/docs/latest/commands/scan/) glob patterns. Only keys matching at least one pattern are copied. ```json { "copy": { "mode": "all", "patterns": ["user:*", "session:*"] } } ``` In this example, only keys prefixed with `user:` or `session:` are copied; everything else is left out of the branch. {% hint style="info" %} Redis has no schema, so there is no `"schema"` copy mode - only `"empty"` and `"all"` are available. Filtering is done by key pattern rather than by SQL query. {% endhint %} ### TLS-Enabled Custom Images By default the operator starts a remote branch pod with its own `redis-server` command, so TLS configuration baked into a custom image is not picked up and the branch serves plain TCP. If your apps connect to Redis over TLS (or your platform requires it), configure the branch pod via the `operator.redisBranchConfig` value in the [mirrord-operator Helm chart](https://github.com/metalbear-co/charts/blob/main/mirrord-operator/values.yaml): ```yaml redisBranchConfig: dbPod: image: registry: "myregistry/redis-tls" # custom image with certificates baked in dbServerArgs: # appended to the operator's redis-server command - "--tls-port" - "6379" - "--port" - "0" - "--tls-cert-file" - "/certs/tls.crt" - "--tls-key-file" - "/certs/tls.key" - "--tls-auth-clients" - "no" tls: true # the operator connects to the branch over TLS ``` The two settings play different roles: * `dbServerArgs` - extra flags appended to the branch's `redis-server` command, after the operator-managed `--requirepass`. Use them to enable the TLS listener with the certificate paths that exist inside your image. * `tls` - tells the **operator** that the branch only accepts TLS: the data-copy step connects over TLS, and the connection URL injected into your app uses the `rediss://` scheme. Requirements: * Keep the TLS listener on the default port (`--tls-port 6379`) and disable the plaintext listener (`--port 0`). The operator always points your app and its own data-copy step at port `6379` on the branch pod. * The certificate paths passed in `dbServerArgs` must exist inside the image - build them into your custom Redis image, since the operator does not mount certificate volumes into branch pods. * The config applies when a branch is **created**; branches that already exist keep the mode they started with. {% hint style="info" %} TLS branch pods require operator and Helm chart `3.183.0` or later. Local Redis branches are unaffected - they always run a plain local instance. {% endhint %} ### Local Redis mirrord can spin up a local Redis instance, automatically redirecting your app's Redis traffic to it. ```json { "feature": { "db_branches": [ { "type": "redis", "location": "local", // "remote" (default) or "local" "connection": { // Use "host" if your app reads Redis as host:port (e.g. REDIS_ADDR=redis:6379) // Use "url" if your app reads a full Redis URL (e.g. REDIS_URL=redis://user:pass@redis:6379/0) "host": { "type": "env", "variable": "REDIS_ADDR" } }, "local": { // Optional runtime config "port": 6379, // Custom port (default: 6379) "runtime": "container", // "container" (default), "redis_server", or "auto" "container_runtime": "docker" // "docker" (default), "podman", or "nerdctl" } } ] } } ``` mirrord overrides the env variable to point to `localhost:` and cleans up the Redis instance on exit. Notes on local branches: * A local branch always starts empty - copy modes do not apply. * The `id` field is not used for local Redis instances and has no effect on database selection or reuse. * `local.port`: Sessions that use the same port share a single local Redis database. When a new session starts on that port, it creates a new database instance that replaces the existing one. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://metalbear.com/mirrord/docs/sharing-the-cluster/db-branching/redis.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.