We have a HAProxy which balances reads and writes to only one (of three) Galera nodes.
If this balancing works fine, the parameters
cert.log_conflicts should never log any conflicts and errors? It won't fill up /var/log filesystem with messages?
What is the drawback of enabling
cert.log_conflicts? Why it's not enabled by default?
Please give more info, the only thing I found was DEALING WITH MULTI-MASTER CONFLICTS
Lastly, you can enable conflict logging features through wsrep_log_conflicts and cert.log_conflicts.
# Enable Conflict Logging wsrep_log_conflicts=ON wsrep_provider_options="cert.log_conflicts=YES"
These parameters enable different forms of conflict logging on the database server. When turned on, the node logs additional information about the conflicts it encounters, such as the name of the table and schema where the conflict occurred and the actual values for the keys that produced the conflict.
7:51:13 [Note] WSREP: trx conflict for key (1,FLAT8)056eac38 0989cb96: source: cdeae866-d4a8-11e3-bd84-479ea1a1e941 version: 3 local: 1 state: MUST_ABORT flags: 1 conn_id: 160285 trx_id: 29755710 seqnos (l: 643424, g: 8749173, s: 8749171, d: 8749171, ts: 12637975935482109) <--X--> source: 5af493da-d4ab-11e3-bfe0-16ba14bdca37 version: 3 local: 0 state: APPLYING flags: 1 conn_id: 157852 trx_id: 26224969 seqnos (l: 643423, g: 8749172, s: 8749171, d: 8749170, ts: 12637839897662340)