From 7f3de77688ef370801724dad919beac3bcfeb6d4 Mon Sep 17 00:00:00 2001 From: Denys Fedoryshchenko Date: Sun, 14 May 2023 21:49:17 +0300 Subject: [PATCH] Add more notes --- networking.md | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/networking.md b/networking.md index 3dd0f94..6054393 100644 --- a/networking.md +++ b/networking.md @@ -21,4 +21,32 @@ ip link set dev eth5 up ip link set dev eth6 up ip link set dev eth7 up ip link set dev bond0 up -``` \ No newline at end of file +``` + +## Troubleshooting + +### Packetloss + +* This kind of fast ping need to be applied only on ethernet links with MTU 1500. No packetloss should be present. +``` +ping -c 1000 -i 0.01 -s1472 127.0.0.1 +ping -c 1000 -i 0.01 -s1472 nearby.ip +``` + +* Check if any dropped counter are increasing +``` +tc -s -d qdisc show +``` + +* Check SFP signal level (if SFP supports DDM/DOM) +``` +ethtool -m eth4 +``` + +You might need to tune icmp rate limit if too many people ping this host: +``` +net.ipv4.icmp_msgs_per_sec = 10000 +net.ipv4.icmp_ratelimit = 100000 +net.ipv4.icmp_msgs_burst=1000 +``` +