[SOLVED] Too many close_wait - lxc with apache debian 10

[aballi1]

Hi,

maybe someone can help me.

System:
Proxmox 6.0-9 (latest update)
lxc with Debian 10
Firewall currently disabled (was enabled)
lxc is connected to vmbr0 with an own IP address

i tried to move a dedicated webserver (with debian 9 and apache) to an lxc setup.
mostly everyting works fine, expcept that i have to restart apache every 30-60 sec. because i get too many close_wait TCP connections.

Example:

apache2 10108 www-data  161u  IPv4 37387495      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47812 (CLOSE_WAIT)
apache2 10152 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10152 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10152 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10152 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10152 www-data  161u  IPv4 37387522      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47814 (CLOSE_WAIT)
apache2 10159 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10159 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10159 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10159 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10159 www-data  161u  IPv4 37387528      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47822 (CLOSE_WAIT)
apache2 10160 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10160 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10160 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10160 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10160 www-data  161u  IPv4 37372553      0t0  TCP lxc-apache01.server.host:https->185.6.9.216:41452 (CLOSE_WAIT)
apache2 10174 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10174 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10174 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10174 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10174 www-data  161u  IPv4 37372559      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47832 (CLOSE_WAIT)
apache2 10175 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10175 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10175 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10175 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10175 www-data  161u  IPv4 37416014      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47838 (CLOSE_WAIT)
apache2 10180 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10180 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10180 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10180 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10180 www-data  161u  IPv4 37388424      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47840 (CLOSE_WAIT)
apache2 10181 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10181 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10181 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10181 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10181 www-data  161u  IPv4 37388425      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47842 (CLOSE_WAIT)
apache2 10195 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10195 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10195 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10195 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10195 www-data  161u  IPv4 37387538      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47844 (CLOSE_WAIT)
apache2 10196 www-data    7u  IPv4 37303616      0t0  TCP localhost:https (LISTEN)
apache2 10196 www-data    8u  IPv4 37303618      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10196 www-data    9u  IPv6 37303620      0t0  TCP lxc-apache01:https (LISTEN)
apache2 10196 www-data   10u  IPv4 37303622      0t0  TCP lxc-apache01.server.host:https (LISTEN)
apache2 10196 www-data  161u  IPv4 37387539      0t0  TCP lxc-apache01.server.host:https->lxc-apache01.server.host:47846 (CLOSE_WAIT)

First i thought it is maybe the firewall setup, but i deactivated the firewall i have still the same issue.
on another container (same host, same setup of the container except that instead of apache, nginx is running) i don't have this problem.

Maybe anyone has an idea ?

Best, aballi1

 

[Alwin]

May you please be so kind and post the solution, so other can benefit?

 

[aballi1]

It was not related to proxmox at all. - It was related to a missing Perl Date::Format extenstion, which prevented Apache to close the connection. (Looks like a bug in Apache).