On Tue, 03 Nov 2009 16:21:04 +0100, "Dawid Sieradzki / Gadu-Gadu S.A." <[email protected]> wrote: > Hi, > > Mysql persistent tcp balance problem. > > MYSQL CLIENT ---- [CONN A] ----> LB TCP ---- [CONN B] ----> MYSQL > DAEMON > > When we did error on MYSQL daemon site (CONN B - BACKEND IS MARKED AS > DOWN), haproxy will switch new connection to another mysql daemon. > But current connections (CONN A) stay on broken line (CONN B) > > The question is how to switch current mysql client connections hanged > on haproxy to new MYSQL backend ? > > Greetings > You mean situation that 1.App is connecting [CONN A] 2.Does some queries 3.Then backend dies 4.Application wants to do more queries but backend dont respond and timeout after x seconds, then app sends "DB connection refused" ??
If yes, only way (IMO) to do it in haproxy (as it knows nothing about
MySQL protocol) is:
1.set a short timeouts, like 10s
2.make application code like:
execute_query();
if (query_failed() && we_tried_to_reconnect_less_than_5_times()) {
reconnect;
try_query again
}
so when connection dies, instead of failin request it tries again and
get dispatched to other backen
PS. Jak wyłączyć w gg filtrowanie URLi od nieznajomych ? :D:D
--
Mariusz Gronczewski (XANi) <[email protected]>
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