| Support Status | Test Case |
|---|---|
| Production | 1 |
replication-manager supports 2-node multi-master topology detection. It is required to declare it explicitely in the configuration.
replication-multi-master (2.0), multimaster (0.7)| Item | Value |
|---|---|
| Description | Enable Master-Master topology |
| Type | boolean |
| Default Value | false |
You just need to set one preferred master.
We advise to enable restart of database in read-only mode to cover the case where a failed node tries to rejoin but can't be contacted anymore from replication-manager, in such case no write traffic will be enabled on the rejoining node. In a Multi DC split brain with a proxy on each side, we can simply ensure the split brain will not make the database diverge on each side.
MariaDB configuration file:
read_only = 1This flag ensures that in case of split brain + leader crash, when old leader is reintroduced it will not show up as a possible leader for WRITES.
MaxScale configuration file:
Maxscale needs to be instructed to monitor multi-master, the following settings tracks the read-only flag and routes queries to the writable node.
[Multi-Master Monitor]
type=monitor
module=mmmon
servers=server1,server2,server3
user=myuser
passwd=mypwd
detect_stale_master=true