confuser
commented
8 years ago There's not really very much I can do to handle this scenario, albeit rare.
Closed EvilOlaf closed 8 years ago
confuser
commented
8 years ago There's not really very much I can do to handle this scenario, albeit rare.
EvilOlaf
commented
8 years ago Maybe BM should not give up reconnecting to the database if it was connected once since server startup. Could be delayed by a few seconds between each try though.
confuser
commented
8 years ago Perhaps, but then that causes other problems. For those running with checkOnJoin, does BM then fallback to memory checks? Do we still allow players to join if they're not banned in memory? What about new bans that are then not synced? We're then letting players join that shouldn't, and so on.
EvilOlaf
commented
8 years ago I actually do not really understand why it might be a good idea to give up connecting to the database especially when checkOnJoin is used.
The only problem I see here is that no one ingame (with proper permission node) gets a warning that the database connection has been dropped and could not be reestablished yet (check your logs!).
confuser
commented
8 years ago The problem is, the connection will timeout in X seconds, which will prevent players from joining, with checkOnJoin.
If the plugin fails on startup to connect, it can't pull all the ban data into memory, meaning banned players would be allowed to join, muted players would be allowed to talk etc. This is the main reason for having a stable MySQL connection.
EvilOlaf
commented
8 years ago I am aware that having a stable connection to the database is important in almost all cases software need something to store its data. It is also clear that the server owner or system administrator has to guarantee this stability.
Maybe this is the wrong way to get to a point. Lets try another. I did not test this so what happens if the database connection drops and can not be reestablished within 10 retries? Regardless of checkOnJoin.
confuser
commented
8 years ago Sorry seem to have missed this
Maybe this is the wrong way to get to a point. Lets try another. I did not test this so what happens if the database connection drops and can not be reestablished within 10 retries? Regardless of checkOnJoin.
Then whatever query that it was attempting, will fail and throw an exception, halting anything it was doing i.e. running a command, performing a sync etc. Anything else after that which causes a query to run against the database will try to connect again, and so on, resulting in an endless 'attempting to connect' cycle as shown above.
EvilOlaf
commented
8 years ago So basically there are more than 10 retries?
confuser
commented
8 years ago There are 10 retries per query.
I recently updated my MySQLd while CB was running. Not the smartest idea, I know but it was at the development machine, so I did not care.
Anyway, took a while till the MySQLd was up again and meanwhile BM tried 10 times to reconnect and gave up. So far, so good.
Then I decided to restart the server in order to make all database using plugins and stuff work properly again.
Had to send a
SIGTERMto the java process to stop it. Still on BM5.7.2. I know there was a switch at the MySQL backend, so this might not be happen in this form again but maybe interesting to know anyways. Spigot 1.8.8