From de020be72a8467b44c07c5e0a8d3b36fc664573b Mon Sep 17 00:00:00 2001 From: Denys Fedoryshchenko Date: Thu, 3 Aug 2023 20:14:33 +0300 Subject: [PATCH] Add neigh tuning --- PPPOE_management.md | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/PPPOE_management.md b/PPPOE_management.md index f4c268b..d01479d 100644 --- a/PPPOE_management.md +++ b/PPPOE_management.md @@ -349,6 +349,22 @@ As you can see there are 3 other PPPoE servers in the network, and they are all If you see message about "PCIe bandwidth, limited" this means your slot is likely have limited lanes and cannot reach full capacity. In case of X520 cards, this means about 15Gbit total bandwidth limit (in+out). Try to change slot or make sure riser have support for all PCIe lanes. +## Misc tuning + +### Neighbour table overflow + +If you see in dmesg: +``` +[ 803.123253] neighbour: arp_cache: neighbor table overflow! +``` +Apply following tuning: +``` +echo 2560 > /proc/sys/net/ipv4/neigh/default/gc_thresh1  +echo 5120 > /proc/sys/net/ipv4/neigh/default/gc_thresh2 +echo 10240 > /proc/sys/net/ipv4/neigh/default/gc_thresh3 +``` + + ### References