Kernel log: very high number of warnings

General system Kernel, boot, graphics & hardware
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Welcome! Yesterday I became interested in kernel logs. I found quite a lot of repeated warnings with this content: <warn> [1671966479.2430] ipv6ll[5d2a7fad47f9fccb,ifindex=2]: changed: no IPv6 link local address to retry after Duplicate Address Detection failures (back off) and many others such as: <warn> [1671966563.2964] platform-linux: do-add-ip6-address[2: fe80::eb67:f321:482e:4639]: failure 95 (Operacja nie obsługiwana)

 [UFW AUDIT] IN= OUT=wlan0 SRC=192.168.1.115 DST=172.65.229.194 LEN=52 TOS=0x00 PREC=0x00 TTL=64 ID=9568 DF PROTO=TCP SPT=59680 DPT=443 WINDOW=501 RES=0x00 ACK URGP=0 [/code] [code] [UFW AUDIT] IN=wlan0 OUT= MAC=1c:65:9d:86:b5:ea:a0:c5:62:74:41:70:08:00 SRC=172.217.16.14 DST=192.168.1.115 LEN=125 TOS=0x00 PREC=0x80 TTL=121 ID=17244 PROTO=TCP SPT=443 DPT=34704 WINDOW=261 RES=0x00 ACK PSH URGP=0

These warnings are many and follow very quickly in succession. I have not noticed such notification activity before, similarly, my other computer running Debian does not display so many warnings. I know that some are related to my internal network traffic, but a few are related to incoming connections. Could someone explain to me what is going on and how to possibly subdue it? If more log results are needed, I will provide.

Edit: I didn’t pay attention that I had the ipv6 protocol disabled in Grub. That’s probably why there were so many of those warnings. After removing the entry, there are fewer warnings and they only apply to firewall rules.

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The reality is I wouldn’t get too concerned about playing whack-a-mole with the warnings / errors proactively. You’ll spend a lot of time chasing basically nothing. Use it as a tool to help resolve issues when they arrive and let it do its thing otherwise.

1 Like
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I realize that the analysis is without purpose. Just wondering why there has been so much activity in these warnings recently. At first it was not so. Well, and on Debian, the logs are only about blocking the connections in question, without the audited ones

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Disable firewall.

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Ok gentlemen, in the meantime I will leave this topic, because nothing sensible can be thought of. I’ll try to explore more about iptables or nftables and then I’ll let you know. Thanks for your interest!