Connections "CLOSE_WAIT" that never close

[Alexandre]

Hello everyone,

for some time, we have connections "CLOSE_WAIT" that never close. We
use Akamai front of Varnish for many applications.

I adjusted my sysctl.conf but it does not work for this application.
---
net.ipv4.tcp_keepalive_time = 60
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_keepalive_probes = 20
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
---

Do you have an idea to fix this problem?

Regards,
Alexandre.

---
tcp        1      0 my_server:7042         88.221.82.37:52443
CLOSE_WAIT  18187/varnishd tcp        1      0 my_server:7042
2.16.117.87:36012       CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         95.101.182.125:43760    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
92.123.226.166:58796    CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:52244      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.113.45:59244     CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:53067      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.113.45:54092     CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         95.101.182.150:62044    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.113.45:59123     CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         92.123.226.166:40948    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
173.223.10.118:51051    CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         95.101.182.125:53566    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.16.117.103:39918      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         173.223.10.118:54579    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.181:45599      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:45879      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.159:61824      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:59291      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.159:37456      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:50724      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:52487      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         95.101.182.143:42309    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.112.246:41614    CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:41737      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.181:46179      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:62914      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:52647      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         88.221.112.246:37128    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.159:58640      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         92.123.226.174:56061    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:63367      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.159:34843      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:35159      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         173.223.10.118:46862    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.112.246:34340    CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:46095      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.159:46841      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         92.123.226.174:45993    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:45478      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:43897      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:40259      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         92.123.226.174:39482    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.119:52310      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         88.221.112.246:62295    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.22.112.159:60489      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:37733      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.82.14:35025      CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:42471      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.16.117.92:62335       CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         88.221.82.14:59443      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
92.123.226.166:55261    CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         92.123.226.166:48501    CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
2.18.244.28:64960       CLOSE_WAIT  18187/varnishd tcp        1      0
my_server:7042         2.22.112.119:59856      CLOSE_WAIT
18187/varnishd tcp        1      0 my_server:7042
88.221.82.37:64593 CLOSE_WAIT  18187/varnishd  
---