My darling wife got a new iPad2 for the holidays. Â Worked fine while we were out of the house … but as soon as we got home, the Facebook Chat (messaging) feature stopped working, and hung with a permanent “connecting”. Â In case you’re not following, “chat” is what shows up in the right-hand column when you use Facebook for the iPad (latest version as of December 2011) in landscape mode (and only shows up in landscape mode). Â To restate the problem (and help indexing <g>): Â Facebook Chat (aka Facebook Messaging) on the iPad (right-most pane in landscape mode) hung with a “Connecting …” message due to firewall port blocking.
When I connected outside my firewall (directly to my DSL connection) it worked; it didn’t work from behind my firewall. Â So … clearly a ports issue … but what ports?
Drove myself crazy trying to figure this out. Â Nothing I could find by Googling. Â Closest I could come was that Facebook Chat might be using XMPP (TCP ports 5222 and 5223), which makes sense … but opening those ports did nothing to solve the problem.
Eventually, I turned off the firewall (yikes) and turned on WireShark and ran the app. Â Doing so, I saw a very strange pattern — connections to Facebook servers on port 8883, which is, technically, the “secure MQTT” port. Â Long story short, I enabled TCP port 8883, and Facebook Chat suddenly started working.
Some additional notes:
- I left XMPP (ports 5222 and 5223) enabled … so you might also need these ports, in addition to 8883.
- 8883 is strange! Â The only meaningful reference I could find was that SameTime, that old Lotus Notes IM app, used it. Â Maybe someone at Facebook pilfered some old SameTime code?
If this helps you out, please leave a comment … I’m curious to know who else has encountered this, whether it’s something unique to me, or I just happened to stumble on it first!