Change usage of Redis slave to replica

* This was renamed in Redis 5.0, and will eventually be removed

https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/5141

config/redis.cache.yml.example

@@ -10,7 +10,7 @@ development:
   #     host: localhost
   #     port: 26380 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26380 # point to sentinel, not to redis port
 test:
   url: redis://localhost:6379/10
@@ -31,8 +31,8 @@ production:
   # url: redis://master:6380
   # sentinels:
   #   -
-  #     host: slave1
+  #     host: replica1
   #     port: 26380 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26380 # point to sentinel, not to redis port

config/redis.queues.yml.example

@@ -10,7 +10,7 @@ development:
   #     host: localhost
   #     port: 26381 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26381 # point to sentinel, not to redis port
 test:
   url: redis://localhost:6379/11
@@ -31,8 +31,8 @@ production:
   # url: redis://master:6381
   # sentinels:
   #   -
-  #     host: slave1
+  #     host: replica1
   #     port: 26381 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26381 # point to sentinel, not to redis port

config/redis.shared_state.yml.example

@@ -10,7 +10,7 @@ development:
   #     host: localhost
   #     port: 26382 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26382 # point to sentinel, not to redis port
 test:
   url: redis://localhost:6379/12
@@ -31,8 +31,8 @@ production:
   # url: redis://master:6382
   # sentinels:
   #   -
-  #     host: slave1
+  #     host: replica1
   #     port: 26382 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26382 # point to sentinel, not to redis port

config/resque.yml.example

@@ -8,7 +8,7 @@ development:
   #     host: localhost
   #     port: 26380 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26381 # point to sentinel, not to redis port
 test:
   url: redis://localhost:6379
@@ -27,8 +27,8 @@ production:
   # url: redis://master:6379
   # sentinels:
   #   -
-  #     host: slave1
+  #     host: replica1
   #     port: 26379 # point to sentinel, not to redis port
   #   -
-  #     host: slave2
+  #     host: replica2
   #     port: 26379 # point to sentinel, not to redis port

doc/administration/high_availability/redis_source.md

@@ -40,7 +40,7 @@ This is the section where we install and set up the new Redis instances.
 - Since Redis 3.2, you must define a password to receive external connections
   (`requirepass`).
 - If you are using Redis with Sentinel, you will also need to define the same
-  password for the slave password definition (`masterauth`) in the same instance.
+  password for the replica password definition (`masterauth`) in the same instance.
 
 In addition, read the prerequisites as described in the
 [Omnibus Redis HA document](redis.md#prerequisites) since they provide some
@@ -72,9 +72,9 @@ Assuming that the Redis master instance IP is `10.0.0.1`:
 
 1. Restart the Redis service for the changes to take effect.
 
-### Step 2. Configuring the slave Redis instances
+### Step 2. Configuring the replica Redis instances
 
-Assuming that the Redis slave instance IP is `10.0.0.2`:
+Assuming that the Redis replica instance IP is `10.0.0.2`:
 
 1. [Install Redis](../../install/installation.md#7-redis).
 1. Edit `/etc/redis/redis.conf`:
@@ -95,12 +95,12 @@ Assuming that the Redis slave instance IP is `10.0.0.2`:
    requirepass redis-password-goes-here
    masterauth redis-password-goes-here
 
-   ## Define `slaveof` pointing to the Redis master instance with IP and port.
-   slaveof 10.0.0.1 6379
+   ## Define `replicaof` pointing to the Redis master instance with IP and port.
+   replicaof 10.0.0.1 6379
    ```
 
 1. Restart the Redis service for the changes to take effect.
-1. Go through the steps again for all the other slave nodes.
+1. Go through the steps again for all the other replica nodes.
 
 ### Step 3. Configuring the Redis Sentinel instances
 
@@ -131,7 +131,7 @@ master with IP `10.0.0.1` (some settings might overlap with the master):
    masterauth redis-password-goes-here
 
    ## Define with `sentinel auth-pass` the same shared password you have
-   ## defined for both Redis master and slaves instances.
+   ## defined for both Redis master and replicas instances.
    sentinel auth-pass gitlab-redis redis-password-goes-here
 
    ## Define with `sentinel monitor` the IP and port of the Redis
@@ -149,18 +149,18 @@ master with IP `10.0.0.1` (some settings might overlap with the master):
    ##   already tried against the same master by a given Sentinel, is two
    ##   times the failover timeout.
    ##
-   ## * The time needed for a slave replicating to a wrong master according
+   ## * The time needed for a replica replicating to a wrong master according
    ##   to a Sentinel current configuration, to be forced to replicate
    ##   with the right master, is exactly the failover timeout (counting since
    ##   the moment a Sentinel detected the misconfiguration).
    ##
    ## * The time needed to cancel a failover that is already in progress but
-   ##   did not produced any configuration change (SLAVEOF NO ONE yet not
-   ##   acknowledged by the promoted slave).
+   ##   did not produced any configuration change (REPLICAOF NO ONE yet not
+   ##   acknowledged by the promoted replica).
    ##
-   ## * The maximum time a failover in progress waits for all the slaves to be
-   ##   reconfigured as slaves of the new master. However even after this time
-   ##   the slaves will be reconfigured by the Sentinels anyway, but not with
+   ## * The maximum time a failover in progress waits for all the replicas to be
+   ##   reconfigured as replicas of the new master. However even after this time
+   ##   the replicas will be reconfigured by the Sentinels anyway, but not with
    ##   the exact parallel-syncs progression as specified.
    sentinel failover_timeout 30000
    ```
@@ -203,7 +203,7 @@ setup:
 
 1. [Restart GitLab](../restart_gitlab.md#installations-from-source) for the changes to take effect.
 
-## Example of minimal configuration with 1 master, 2 slaves and 3 Sentinels
+## Example of minimal configuration with 1 master, 2 replicas and 3 Sentinels
 
 In this example we consider that all servers have an internal network
 interface with IPs in the `10.0.0.x` range, and that they can connect
@@ -215,13 +215,13 @@ outside ([Internet](https://gitlab.com/gitlab-org/gitlab-foss/uploads/c4cc8cd353
 
 For this example, **Sentinel 1** will be configured in the same machine as the
 **Redis Master**, **Sentinel 2** and **Sentinel 3** in the same machines as the
-**Slave 1** and **Slave 2** respectively.
+**Replica 1** and **Replica 2** respectively.
 
 Here is a list and description of each **machine** and the assigned **IP**:
 
 - `10.0.0.1`: Redis Master + Sentinel 1
-- `10.0.0.2`: Redis Slave 1 + Sentinel 2
-- `10.0.0.3`: Redis Slave 2 + Sentinel 3
+- `10.0.0.2`: Redis Replica 1 + Sentinel 2
+- `10.0.0.3`: Redis Replica 2 + Sentinel 3
 - `10.0.0.4`: GitLab application
 
 Please note that after the initial configuration, if a failover is initiated
@@ -257,7 +257,7 @@ or a failover promotes a different **Master** node.
 
 1. Restart the Redis service for the changes to take effect.
 
-### Example configuration for Redis slave 1 and Sentinel 2
+### Example configuration for Redis replica 1 and Sentinel 2
 
 1. In `/etc/redis/redis.conf`:
 
@@ -266,7 +266,7 @@ or a failover promotes a different **Master** node.
    port 6379
    requirepass redis-password-goes-here
    masterauth redis-password-goes-here
-   slaveof 10.0.0.1 6379
+   replicaof 10.0.0.1 6379
    ```
 
 1. In `/etc/redis/sentinel.conf`:
@@ -282,7 +282,7 @@ or a failover promotes a different **Master** node.
 
 1. Restart the Redis service for the changes to take effect.
 
-### Example configuration for Redis slave 2 and Sentinel 3
+### Example configuration for Redis replica 2 and Sentinel 3
 
 1. In `/etc/redis/redis.conf`:
 
@@ -291,7 +291,7 @@ or a failover promotes a different **Master** node.
    port 6379
    requirepass redis-password-goes-here
    masterauth redis-password-goes-here
-   slaveof 10.0.0.1 6379
+   replicaof 10.0.0.1 6379
    ```
 
 1. In `/etc/redis/sentinel.conf`:

doc/development/scalability.md

@@ -214,7 +214,7 @@ Redis process.
 Single-core: Like PgBouncer, a single Redis process can only use one
 core. It does not support multi-threading.
 
-Dumb secondaries: Redis secondaries (aka slaves) don't actually
+Dumb secondaries: Redis secondaries (aka replicas) don't actually
 handle any load. Unlike PostgreSQL secondaries, they don't even serve
 read queries. They simply replicate data from the primary and take over
 only when the primary fails.
@@ -231,8 +231,8 @@ election to determine a new leader.
 No leader: A Redis cluster can get into a mode where there are no
 primaries. For example, this can happen if Redis nodes are misconfigured
 to follow the wrong node. Sometimes this requires forcing one node to
-become a primary via the [`SLAVEOF NO ONE`
-command](https://redis.io/commands/slaveof).
+become a primary via the [`REPLICAOF NO ONE`
+command](https://redis.io/commands/replicaof).
 
 ### Sidekiq
 

spec/fixtures/config/redis_cache_new_format_host.yml

@@ -7,7 +7,7 @@ development:
       host: localhost
       port: 26380 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26380 # point to sentinel, not to redis port
 test:
   url: redis://:mynewpassword@localhost:6380/10
@@ -16,14 +16,14 @@ test:
       host: localhost
       port: 26380 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26380 # point to sentinel, not to redis port
 production:
   url: redis://:mynewpassword@localhost:6380/10
   sentinels:
     -
-      host: slave1
+      host: replica1
       port: 26380 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26380 # point to sentinel, not to redis port

spec/fixtures/config/redis_new_format_host.yml

@@ -7,7 +7,7 @@ development:
       host: localhost
       port: 26379 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26379 # point to sentinel, not to redis port
 test:
   url: redis://:mynewpassword@localhost:6379/99
@@ -16,14 +16,14 @@ test:
       host: localhost
       port: 26379 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26379 # point to sentinel, not to redis port
 production:
   url: redis://:mynewpassword@localhost:6379/99
   sentinels:
     -
-      host: slave1
+      host: replica1
       port: 26379 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26379 # point to sentinel, not to redis port

spec/fixtures/config/redis_queues_new_format_host.yml

@@ -7,7 +7,7 @@ development:
       host: localhost
       port: 26381 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26381 # point to sentinel, not to redis port
 test:
   url: redis://:mynewpassword@localhost:6381/11
@@ -16,14 +16,14 @@ test:
       host: localhost
       port: 26381 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26381 # point to sentinel, not to redis port
 production:
   url: redis://:mynewpassword@localhost:6381/11
   sentinels:
     -
-      host: slave1
+      host: replica1
       port: 26381 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26381 # point to sentinel, not to redis port

spec/fixtures/config/redis_shared_state_new_format_host.yml

@@ -7,7 +7,7 @@ development:
       host: localhost
       port: 26382 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26382 # point to sentinel, not to redis port
 test:
   url: redis://:mynewpassword@localhost:6382/12
@@ -16,14 +16,14 @@ test:
       host: localhost
       port: 26382 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26382 # point to sentinel, not to redis port
 production:
   url: redis://:mynewpassword@localhost:6382/12
   sentinels:
     -
-      host: slave1
+      host: replica1
       port: 26382 # point to sentinel, not to redis port
     -
-      host: slave2
+      host: replica2
       port: 26382 # point to sentinel, not to redis port

spec/support/redis/redis_shared_examples.rb

@@ -150,7 +150,7 @@ RSpec.shared_examples "redis_shared_examples" do
 
       it 'returns an array of hashes with host and port keys' do
         is_expected.to include(host: 'localhost', port: sentinel_port)
-        is_expected.to include(host: 'slave2', port: sentinel_port)
+        is_expected.to include(host: 'replica2', port: sentinel_port)
       end
     end