sendmsg: operation not permitted

drobble · 09-20-2020, 12:16 PM

Hiya,

after I upgraded Mint 19.3 to Mint 20.0 the networking didn't work anymore.
When trying to connect to my router (ping 192.168.1.1) or to my NAS (ping 192.168.1.105) I receive the message "ping: sendmsg: Operation not permitted".
When ping'ing 80.80.80.80 the ping works and packets coming back.
Access to the web through browser works fine.
Even after I reversed through Timeshift back to Mint 19.3, I still can't access the router and the NAS.

Any help much appreciated.
TIA

Fred

berndbausch · 09-21-2020, 05:05 AM

When you search the internet for this error message, you will find that the most likely cause is blocked ICMP traffic. Therefore, the first thing you should check is your netfilter rule set. I don't know how they are handled in Mint, but as a first step you could try iptables -L or iptables -S, or iptables-save to generate the list of filter rules. Focus on the OUTPUT chain and check for a rule that blocks outgoing ICMP traffic.