CrashPlan is by far my favorite tool for backing up my computers. I'm never able or willing to plug my laptop in to my backup harddrive for long enough for Time Machine to do its job, all of attempts to make Time Machine work over the network (proxied through my always-on desktop) failed. I'm not rich enough to go around buying Apple's Time Capsules or Airport Extremes (I save my money to buy all of Apple's other hardware). CrashPlan, on the other hand, has been a great solution because it actually does a good job of backing up over the internet and I can backup between machines that I own at different sites for free. However, I've been having problems getting the CrashPlan UI App working for a while.
CrashPlan's documentation was largely unhelpful for diagnosing my problem, so here's some things that I learned and what to look for if you're experiencing similar problems.
The error:
In my case, not only was the main CrashPlan app unable to connect to the service, but the CrashPlan MenuBar icon was also greyed out and said it couldn't connect to the backup service.
The environment:
I have been seeing this from OSX Yosemite, but I did have a problem with this a while back on Mavericks, too, so this may be useful for both. For a while it was intermittent, solved by rebooting, but then it became a problem all the time.
The solution(s):
CrashPlan's troubleshooting page for this error had me try a bunch of things, to no avail. Partly, I think it is because of outdated commands for OSX.
First of all, restarting the service using launchctl didn't make any difference.
Second, it wasn't an out-of-memory crashing problem, because the service was still running. To check, I did something like the following (from the Terminal):
> ps aux | grep CrashPlan
bholt 56615 0.0 1.9 6066736 155984 ?? S 4:24PM 0:20.74 /Applications/CrashPlan.app/Contents/MacOS/CrashPlan
root 56587 0.0 0.8 3817772 68128 ?? SNs 4:24PM 0:11.25 /Applications/CrashPlan.app/Contents/MacOS/CrashPlanService -Dapp=CrashPlanService -Xmn10m -Xms15m -Xmx1024m -DappBaseName=CrashPlan -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djava.net.preferIPv4Stack=true -Dsun.net.inetaddr.ttl=300 -Dnetworkaddress.cache.ttl=300 -Dsun.net.inetaddr.negative.ttl=0 -Dnetworkaddress.cache.negative.ttl=0 -DCP_USER_NAME= -DCP_USER_HOME=/Users/bholt -cp lib/com.backup42.desktop.jar:lang com.backup42.service.CPService CP_USER_NAME= CP_USER_HOME=/Users/bholt
bholt 56424 0.0 0.1 894428 11484 ?? SN 4:22PM 0:02.09 /Applications/CrashPlan.app/Contents/Helpers/CrashPlan menu bar.app/Contents/MacOS/CrashPlan menu bar
bholt 59420 0.0 0.0 2451204 696 s006 S+ 7:19PM 0:00.00 grep CrashPlan
You can clearly see the CrashPlanService, run by root, chugging along.
Third, I tried checking the ports for conflicts. Spoiler: turns out this was actually the problem, but their troubleshooting tips weren't helpful, because it turns out the ports were wrong, and the commands were wrong.
They have you check which apps are using which ports with the command:
> sudo lsof -i TCP:4243,4242
>
Which for me returned nil. I had to widen my search:
> sudo lsof -i TCP | grep CrashPlan
CrashPlan 56424 bholt 29u IPv4 0x4c00d1e518e9c329 0t0 TCP localhost:64125->localhost:4243 (ESTABLISHED)
CrashPlan 56424 bholt 30u IPv4 0x4c00d1e518e9c329 0t0 TCP localhost:64125->localhost:4243 (ESTABLISHED)
CrashPlan 56587 root 78u IPv4 0x4c00d1e51a34efe9 0t0 TCP localhost:4200 (LISTEN)
CrashPlan 56587 root 91u IPv4 0x4c00d1e515ec1fe9 0t0 TCP localhost:4200->localhost:64125 (ESTABLISHED)
CrashPlan 56587 root 92u IPv4 0x4c00d1e5172918b9 0t0 TCP ###.###.###.###:64222->central.crashplan.com:https (ESTABLISHED)
CrashPlan 56587 root 93u IPv4 0x4c00d1e51584e4c9 0t0 TCP localhost:4243->localhost:64089 (ESTABLISHED)
CrashPlan 56615 bholt 56u IPv6 0x4c00d1e50ca3ed79 0t0 TCP localhost:64089->localhost:4243 (ESTABLISHED)
Here, I noticed that the CrashPlan service seemed to be trying to use 4200, not 4234 or 4242, which is why my other searches turned up nothing.
I don't know how it happened that CrashPlan was using the wrong ports, but I was able to track down the offending settings that control the ports.
The port the CrashPlan app uses can be controlled by the servicePort setting, but by default it is just set to 4243 (notice here it's commented out because it's using the default):
grep servicePort /Applications/CrashPlan.app/Contents/Resources/Java/conf/ui.properties
# servicePort=4243
The CrashPlanService, on the other hand, is controlled by a servicePort setting in a different configuration file:
> grep servicePort /Library/Application\ Support/CrashPlan/conf/my.service.xml
<servicePort>4200</servicePort>
It looks like the MenuBar app was also assuming 4243, so all I had to do was make sure that they all matched up, by editing the my.service.xml file. If you didn't know, you can open a file in its default editor with the open command:
open /Library/Application\ Support/CrashPlan/conf/my.service.xml
# change line to: <servicePort>4243</servicePort>
And then restart the CrashPlanService using launchctl:
sudo launchctl unload /Library/LaunchDaemons/com.crashplan.engine.plist
sudo launchctl load /Library/LaunchDaemons/com.crashplan.engine.plist
And then everything has been hunky-dory since!
Hope this helps someone else someday!