starlingx/integ
Code Issues Proposed changes

Fix Periodic message loss between VIM and Openstack REST APIs

Browse Source 
set net.ipv4.tcp_tw_recycle=1 to avoid dnat conntrack invalid

The probe connection action before going to time_wait state.
Probe connection
controller               pod        TCP FLAG      SEQ           ACK
controller:50538 ---> endpoint:9292     SYN       2707980036       0
controller:50538 <--- endpoint:9292   SYN ACK     1599414185
2707980037
controller:50538 ---> endpoint:9292     ACK       2707980037
1599414186
controller:50538 ---> endpoint:9292   FIN ACK     2707980037
1599414186
controller:50538 <--- endpoint:9292     ACK       1599414186
2707980038
controller:50538 <--- endpoint:9292   FIN ACK     1599414186
2707980038
controller:50538 ---> endpoint:9292     ACK       2707980038
1599414187

And for the curl command connection with same port 50538: it will be
like
controller              pod          TCP FLAG         SEQ          ACK
controller:50538 -->  service:9292     SYN        2917708674        0
controller:50538 --> endpoint:9292     SYN        2917708674        0
controller:24479 <-- endpoint:9292   SYN ACK      2742336307
2917708675
controller:50538 <-- endpoint:9292   SYN ACK      2742336307
2917708675
controller:50538 -->  service:9292     ACK        2707980038
1599414187
controller:50538 -->  service:9292     ACK        2707980038
1599414187
controller:50538 -->  service:9292     ACK(DROP)  2707980038
1599414187

The last ACK(controller:50538-->service:9292) SEQ and ACK is same as
Probe TIME_WAIT latest ACK’s.
from
https://github.com/torvalds/linux/blob/v3.10/net/ipv4/tcp_ipv4.c#L2002 ,
it only check (des ip , des port, src ip, and src port).Because this is
not
 a correct SEQ/ACK , then it is set invalid and then dropped.

If enabling tcp_tw_recycle, the previous socket should be already
closed, then the issue should be gone.

Closes-Bug: 1817936

Change-Id: If6e66d85f08fc99022946fd2e9f4e5756bfb7b2f
Signed-off-by: Sun Austin <austin.sun@intel.com>
This commit is contained in:
Sun Austin 2019-08-05 16:46:43 +08:00
parent 43fda7f16a
commit 171c43dca8
1 changed files with 2 additions and 1 deletions
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3
base/initscripts-config/files/sysctl.conf
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@ -69,7 +69,8 @@ net.ipv4.conf.all.rp_filter=1
# Limit local port range
net.ipv4.ip_local_port_range = 49216 61000
net.ipv4.tcp_tw_reuse = 1
# Fix https://bugs.launchpad.net/starlingx/+bug/1817936
net.ipv4.tcp_tw_recycle = 1
# WRL
# set max socket memory ; default was 212992
net.core.rmem_max=425984