openstack
/
octavia
Code Issues Proposed changes

Disable conntrack for TCP flows in the amphora 

conntrack is used in the amphora for LVS-based listeners (UDP and
SCTP) and it's enabled by default.
Add nft/iptable rules to disable conntrack for TCP flows, it reduces
memory usage and prevents getting "nf_conntrack: table full, dropping
packet" messages.

Story: 2008979
Task: 42623

Change-Id: Ia15a110c6c5a9b83a29bab56538fa425d994d477
(cherry picked from commit b3f59eeb73)
(cherry picked from commit 1905859662)
This commit is contained in:
Gregory Thiemonge 2021-06-15 09:00:52 +02:00
parent f3b3e35af3
commit c0ad3b347d
2 changed files with 33 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
elements/amphora-agent/static/usr/local/bin/udp-masquerade.sh
View File

@ -36,10 +36,19 @@ if [ "$1" == "add" ]; then
nft add table ip octavia-ipv4
nft add chain ip octavia-ipv4 ip-udp-masq { type nat hook postrouting priority 100\;}
nft add rule ip octavia-ipv4 ip-udp-masq oifname "$3" meta l4proto udp masquerade
nft add chain ip octavia-ipv4 prerouting { type filter hook prerouting priority -300 \; }
nft add rule ip octavia-ipv4 prerouting iifname "$3" meta l4proto tcp notrack
nft add chain ip octavia-ipv4 output { type filter hook output priority -300 \; }
nft add rule ip octavia-ipv4 output oifname "$3" meta l4proto tcp notrack
elif [ "$2" == "ipv6" ]; then
nft add table ip6 octavia-ipv6
nft add chain ip6 octavia-ipv6 ip6-udp-masq { type nat hook postrouting priority 100\;}
nft add rule ip6 octavia-ipv6 ip6-udp-masq oifname "$3" meta l4proto udp masquerade
nft add chain ip6 octavia-ipv6 prerouting { type filter hook prerouting priority -300 \; }
nft add rule ip6 octavia-ipv6 prerouting iifname "$3" meta l4proto tcp notrack
nft add chain ip6 octavia-ipv6 output { type filter hook output priority -300 \; }
nft add rule ip6 octavia-ipv6 output oifname "$3" meta l4proto tcp notrack
else
usage
fi
@ -47,8 +56,14 @@ if [ "$1" == "add" ]; then
else # nft not found, fall back to iptables
if [ "$2" == "ipv4" ]; then
/sbin/iptables -t nat -A POSTROUTING -p udp -o $3 -j MASQUERADE
/sbin/iptables -t raw -A PREROUTING -p tcp -i $3 -j NOTRACK
/sbin/iptables -t raw -A OUTPUT -p tcp -o $3 -j NOTRACK
elif [ "$2" == "ipv6" ]; then
/sbin/ip6tables -t nat -A POSTROUTING -p udp -o $3 -j MASQUERADE
/sbin/ip6tables -t raw -A PREROUTING -p tcp -i $3 -j NOTRACK
/sbin/ip6tables -t raw -A OUTPUT -p tcp -o $3 -j NOTRACK
else
usage
fi
@ -60,9 +75,17 @@ elif [ "$1" == "delete" ]; then
if [ "$2" == "ipv4" ]; then
nft flush chain ip octavia-ipv4 ip-udp-masq
nft delete chain ip octavia-ipv4 ip-udp-masq
nft flush chain ip octavia-ipv4 prerouting
nft delete chain ip octavia-ipv4 prerouting
nft flush chain ip octavia-ipv4 output
nft delete chain ip octavia-ipv4 output
elif [ "$2" == "ipv6" ]; then
nft flush chain ip6 octavia-ipv6 ip-udp-masq
nft delete chain ip6 octavia-ipv6 ip-udp-masq
nft flush chain ip6 octavia-ipv6 prerouting
nft delete chain ip6 octavia-ipv6 prerouting
nft flush chain ip6 octavia-ipv6 output
nft delete chain ip6 octavia-ipv6 output
else
usage
fi
@ -70,8 +93,12 @@ elif [ "$1" == "delete" ]; then
else # nft not found, fall back to iptables
if [ "$2" == "ipv4" ]; then
/sbin/iptables -t nat -D POSTROUTING -p udp -o $3 -j MASQUERADE
/sbin/iptables -t raw -D PREROUTING -p tcp -i $3 -j NOTRACK
/sbin/iptables -t raw -D OUTPUT -p tcp -o $3 -j NOTRACK
elif [ "$2" == "ipv6" ]; then
/sbin/ip6tables -t nat -D POSTROUTING -p udp -o $3 -j MASQUERADE
/sbin/ip6tables -t raw -D PREROUTING -p tcp -i $3 -j NOTRACK
/sbin/ip6tables -t raw -D OUTPUT -p tcp -o $3 -j NOTRACK
else
usage
fi

6
releasenotes/notes/disable-conntrack-for-tcp-01ef6948d99353c2.yaml Normal file
View File

@ -0,0 +1,6 @@
---
fixes:
- |
Disable conntrack for TCP flows in the Amphora, it reduces memory usage for
HAProxy-based listeners and prevents some kernel warnings about dropped
packets.