Hi, Thanks for your prompt reply.
On Fri, Jul 22, 2016 at 7:32 AM, Maxim Dounin <[email protected]> wrote: > Hello! > > On Thu, Jul 21, 2016 at 07:02:48PM -0700, Aditya Umrani wrote: > >> Hello, >> >> I've configured the so_keepalive option for a server (this is also my >> default server). I do have other server configs listening to the same >> port. >> ======== >> listen 9822 default_server so_keepalive=on; >> listen 29822 ssl http2 default_server so_keepalive=on; >> ======== >> >> My sysctl settings are set to : >> ======== >> net.ipv4.tcp_keepalive_time = 120 >> net.ipv4.tcp_keepalive_probes = 10 >> net.ipv4.tcp_keepalive_intvl = 120 >> ======== >> >> However, I see that no tcp keepalive packets are being sent on >> outbound connections (from nginx to the upstream). I also checked the >> output of 'netstat -an --timers' I see that no outbound sockets have >> the 'keepalive' flag. All of them are 'off'. If it matters, the server >> config which actually servers this request is not the default one, but >> one of the other configs. >> I took a quick look at the code and the 'SO_KEEPALIVE' options only >> shows up on functions which deal with listening sockets. Does this >> mean that nginx does not honor this option for outbound connections? > > Yes. The so_keepalive parameter is configured on listening > sockets and applies to connections accepted though these sockets. > > Using SO_KEEPALIVE on sockets to backends are not generally > needed, as these connections are usually local and > well-controlled. (And if it's not the case, many operation > systems have an option to request TCP keepalive for all > connection, like net.inet.tcp.always_keepalive on FreeBSD. > Though looks like Linux isn't able to do so.) I will give it a shot through some LD_PRELOAD tricks. Let me know if anyone has other suggestions. > > -- > Maxim Dounin > http://nginx.org/ > > _______________________________________________ > nginx mailing list > [email protected] > http://mailman.nginx.org/mailman/listinfo/nginx Aditya _______________________________________________ nginx mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx
