[Config] How-to: replicaset configuration

[andreyaksenov]

Previous step: #3851

Product: Tarantool
Since: 3.0
Root document:

• How-to guides | Replication tutorials
• Orphan status
• Replication topologies
• https://www.tarantool.io/en/doc/latest/book/admin/replication/
• https://docs.d.tarantool.io/en/doc/3.0-config-replication/reference/configuration/configuration_reference/
• https://www.tarantool.io/en/doc/latest/reference/reference_lua/box_info/election/
• https://www.tarantool.io/en/doc/latest/reference/reference_lua/box_info/

SME: @ Totktonada

Details

Update the existing tutorials to using a new config.
See the examples in the Replicaset section: https://www.notion.so/tarantool/Getting-Started-with-3-0-03d461efc01c43dd9e09f2bc4903717b

Failover modes: https://github.com/tarantool/tarantool/blob/941a85c39735b789914da04acad3faabd63b5dd6/src/box/lua/config/instance_config.lua#L1068

Election mode (individual nodes):
https://github.com/tarantool/tarantool/blob/941a85c39735b789914da04acad3faabd63b5dd6/src/box/lua/config/instance_config.lua#L1174

Script: https://docs.google.com/document/d/1FoKXJJ3rzhe2D5k6wKrg8uugO8MFs1riREhtcK1hc0U/edit?usp=sharing

Manual failover notes

from @ totktonada:

No leader or leader: null is an important case. A usual master-replica switch process assumes a short period, when all the instances are in RO.

A correct master switch in the failover: manual mode would involve the following steps:

1. Remove the leader key or set it to null.
2. Wait until all the data goes to the future master (compare vclock values).
3. Set the new leader using the leader key.

(BTW, things are pretty same for the failover: off mode if a single master at time is assumed.)

[andreyaksenov]

https://docs.d.tarantool.io/en/doc/3.0/how-to/replication/