Hello there,
I have a small problem with DHCP Server + Client in Virtual Machines using VirtIO network device.
dhcpd: 5 bad udp checksum in 5 packets
I alread read some other forums and mailing list for this problem and it looks like the VirtIO Network Device is not generating correct checksums for outgoing Traffic (or to get more direct they use the host machines checksum to save perfomance for udp packets)
there are some workarounds available were you generate the checksum via iptables for that specific packet type, but it had not worked at my machine(maybe the ports in this line are wrong , tried different ones with dhcp or the exact ports of the protocols, but still no change )
iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill
switching the network device to e1000 solves this problem.
the both machines were fresh debian install and used pretty simple standard configurations, so this may be a real bug in the VirtIO drivers.
Maybe some can confirm that , if you google a bit for the problematic there are lots of threads about it and it should be already fixed since some version?
edit: saw that I posted in the false subforum, can someone move that?
I have a small problem with DHCP Server + Client in Virtual Machines using VirtIO network device.
dhcpd: 5 bad udp checksum in 5 packets
I alread read some other forums and mailing list for this problem and it looks like the VirtIO Network Device is not generating correct checksums for outgoing Traffic (or to get more direct they use the host machines checksum to save perfomance for udp packets)
there are some workarounds available were you generate the checksum via iptables for that specific packet type, but it had not worked at my machine(maybe the ports in this line are wrong , tried different ones with dhcp or the exact ports of the protocols, but still no change )
iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill
switching the network device to e1000 solves this problem.
the both machines were fresh debian install and used pretty simple standard configurations, so this may be a real bug in the VirtIO drivers.
Maybe some can confirm that , if you google a bit for the problematic there are lots of threads about it and it should be already fixed since some version?
edit: saw that I posted in the false subforum, can someone move that?
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