Wikimedia Bugzilla is closed!

deployment-cache-text1 has a vhtcpd purge daemon running with the following options:

 cat /etc/default/vhtcpd 
 DAEMON_OPTS="-F -m 239.128.0.112 -c 127.0.0.1:80 -c 127.0.0.1:3128"

The -m is a multicast address to subscribe to. Since beta does not have multicast, we need vhtcpd to handle request send over unicast.  The daemon does listen on udp:

# netstat -ulnp|grep vhtcpd
udp        0      0 0.0.0.0:4827   0.0.0.0:*      21339/vhtcpd    


When sending a purge request:

$ echo 'https://login.wikimedia.beta.wmflabs.org/' |mwscript purgeList.php --wiki=loginwiki
Purging 1 urls
Done!


We do receive a packet on the varnish cache:


# tcpdump -n -s0 -A udp port 4827
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
12:14:00.440175 IP 10.4.0.58.53582 > 10.4.1.133.4827: UDP, length 77
E..i..@.@.$.
..:
....N...U.r.M...G..I.#.....HEAD.)https://login.wikimedia.beta.wmflabs.org/..HTTP/1.0....
#

But that does not seem to trigger a purge :(  A request before:

$ curl -s -i https://login.wikimedia.beta.wmflabs.org/|grep X-Cache
X-Cache: deployment-cache-text1 hit (11), deployment-cache-text1 frontend hit (9)

And after the purge is send

$ curl -s -i https://login.wikimedia.beta.wmflabs.org/|grep X-Cache
X-Cache: deployment-cache-text1 hit (11), deployment-cache-text1 frontend hit (10)