FreeBSD/mt-daapd/mDNS/Intel PRO 1000 Set Issue

[joedunn]

All, for documentation purposes and to let you all know. Multicast DNS and Intel PRO 1000 nic’s seem to have issues under FreeBSD 7.0.

Link below

http://www.nabble.com/kern-119635:-Bad-UDP-packet-checksum-with-em(4)-and-rxcsum-txcsum-enabled-td14787749.html

Once I set the following to my interface mt-daapd/avahi started to work

ifconfig_em0=”inet XXX.XXX.XXX.XXX netmask 255.255.255.0 -rxcsum -txcsum”

Once you disable checksumming in hardware and allow the OS to do it everything works.

You can see this behavior in a tcpdump and getting bad checksums in mDNS traffic.

Hope this helps, might want to add it to the FreeBSD faq/setup guide for mt-daapd to avoid 3 weeks of troubleshooting 🙂

[Anonymous]

joedunn,

Please describe in more detail the issues you saw with your FreeBSD/mt-daapd/avahi setup before you disabled rx/tx checksumming on the Intel Pro/1000 NIC.

I am running mt-daapd (no avahi) only with FreeBSD 7.0 and an Intel Pro/1000 GT NIC and noticed the mt-daapd iTunes share drops off all iTunes clients after two hours. Restarting the mt-daapd daemon brings them back… for another 2 hours before it disappears.

After running “ifconfig em0 -rxcsum -txcsum” things appear to have stabilized.

Does this reflect your findings?
R.

[Author]

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