On 17.06.15 22:39, Shawn Zhou wrote:
BIND on my resolvers reaches the max open file limit and I am getting lots of SERVFAILs http://pastebin.com/SxRsHLff
After I increased the max-socks (-s 8192) to 8192, I no longer saw the file limit error from the log anymore; however, I am still many SERVFAILs.
no other errors?
Our resolvers were doing about 15k queries per seconds when this was happening and those were legit traffic. I am aware that I am setting recursive clients to a very high number. Those resolvers are running on 12-cores cpu and 24G RAM hardware. cpu utilization was at about 20% and plenty of RAM left.
I am wondering if I've reached the limit of BIND for the amount of recursive queries it can serve. Any other tunings I should try?
maybe changing number of recursive-clients, max-clients-per-query. Does EDNS work for you? EDNS problems often result to increased number of TCP queries which slows down resolution ...
By the way, the resolvers are running RHEL 6.x.
precise BIND version would help a bit more... seems RH6.6 contains 9.8.2 but that may be different for older RH6 versions. -- Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/ Warning: I wish NOT to receive e-mail advertising to this address. Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. LSD will make your ECS screen display 16.7 million colors _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users