Unlockupd
Unlockupd
1.0

0.0

Unlockupd free download for Mac

Unlockupd

1.0
26 September 2005

Works around a bug in lookupd.

Overview

Unlockupd works around a bug in lookupd, a system service which is required for proper operation of Mac OS X. If lookupd fails, the system quickly becomes unusable. Unlockupd periodically checks lookupd's status and forces it to restart should it fail.

WARNING: Although Unlockupd has undergone a significant amount of testing with no reported problems, this software should still be considered beta-quality. It is only being made available now since the cat snuck out of the bag on the darwin-dev mailing list.

Technical Details - Lookupd is the lookup and caching daemon responsible for handling NetInfo, DNS, and other such requests. Applications typically do not access lookupd directly, but rather, use standardized library functions (such as gethostbyname for DNS) which access lookupd on the application's behalf.

Lookupd has a bug (rdar://3632865) in its cache cleanup code that causes it to randomly crash. CrashReporter, the system crash log agent, does not properly handle lookupd crashes and as a result, when lookupd crashes, the process is not terminated. Since lookupd has not terminated, mach_init does not respawn lookupd. From this point, any application that attempts to access lookupd either directly or indirectly, will hang.

Once lookupd stops responding it becomes difficult but not impossible to recover the system to a usable state. One technique which works but is not recommended (for obvious reasons), is to leave a root shell running and `killall -9 lookupd` when it becomes obvious that lookupd has died (sudo does not work, since it requires lookupd's services, as does opening a new terminal window).

How unlockupd works - Unlockupd is a small daemon which periodically polls lookupd. If it detects that lookupd is not responding, it makes a note in the system log and forces lookupd to terminate.

What's new in Unlockupd

If you have already installed Unlockupd 1.0b1, you do not need to install 1.0. The only difference is that the 1.0 download also includes documentation.

6 Unlockupd Reviews

Rate this app:

Anonymous
19 September 2005

Most helpful

Just had this lookupd crash happen to me this morning. Entire system went unresponsive. Couldn't get a Terminal, nor an SSH connection. It seems that turning off the network connection (unplugging the Ethernet cable) managed to unblock whatever that was going on, and at least I got a crash log out of it. Sure enough, the crash logs implicate the lookupd thread that handles caches. I'm irritated that the only workaround for this is having a daemon periodically kill lookupd, but my thanks to the author for thinking of this temporary solution. Come on Apple. Fix the problem already.
Like
Version 1.0b1
Anonymous
01 November 2005
Does anybody know if this Problem is fixed in OSX 10.4.3.?
Like
Version 1.0
3 answer(s)
Anonymous
Anonymous
17 November 2005
Not as yet. I have installed Tiger Server 10.4.3 and while the locks don't happen as frequently, they do still occur.
Like
Version 1.0
Lechter
Lechter
23 November 2005
This saved my behind. I was with Apple Tech Support "Senior" and they were telling me to format my drive. Unlockupd fixed it all right away!!!
Like
Version 1.0
Dmp6
Dmp6
11 January 2006
Any idea if 10.4.4 fixes the problem at last?
Like
Version 1.0
Kballard
29 September 2005
The explanation here isn't matching the issues I'm having with lookupd. Twice now I've had Safari simply stop being able to load web pages. No apps hang, just Safari is sitting there trying to contact the site and never going anywhere. When I unplug my ethernet cable I suddenly get a crash reporter dialog for lookupd, and plugging back in my ethernet cable allows Safari to function once again. Will this program help with this issue, or is this something completely unrelated?
Like
Version 1.0
1 answer(s)
Anonymous
Anonymous
29 September 2005
It probably will help, but it's all academic... until you try it.
Like
Version 1.0
Anonymous
28 September 2005
It would be great if the pkg would also act as an uninstaller rather than requiring terminal commands. Considering its relative simplicity, it would also be nice if the pkg displayed a button to display the ReadMe inside the installer itself.
Like
Version 1.0
1 answer(s)
Sören Kuklau
Sören Kuklau
03 October 2005
Apple's Installer does not currently have uninstallation hook-ins, which is why they use a .command instead. The readme, on the other hand, could indeed have been added.
Like
Version 1.0
Anonymous
26 September 2005
Don't worry about Apple getting around to fixing this, as iTunes takes precedence in their software development. Ever seen iTunes lockup? And you wouldn't. You'll have to learn to live with patches like this until the next software update for the system comes out...whenever that is.
Like
Version 1.0
2 answer(s)
Anonymous
Anonymous
26 September 2005
You are so full of it. And just how do you know about Apple's priorities? Or are you conjuring reality up from your own imagination? BTW, A lot of people do not have any problems related to this lookupd issue, I don't. And the Macs that I provide support for don't either.
Like
Version 1.0
Anonymous
Anonymous
26 September 2005
Oh come on. Your logic doesn't make sense. If this lookupd bug occurs, then iTunes won't be accessible, therefore Apple must fix the lookupd bug just so customers can use iTunes, right? So even by your logic, Apple will have to fix this bug.
Like
Version 1.0
Anonymous
20 September 2005
Wow... I have been trying to figure out my occasional lockups and here is a feasible reason with solution. Thanks for helping to take care of a moderate and occasional issue that has harassed me to no end.
Like
Version 1.0b1
Anonymous
19 September 2005
Just had this lookupd crash happen to me this morning. Entire system went unresponsive. Couldn't get a Terminal, nor an SSH connection. It seems that turning off the network connection (unplugging the Ethernet cable) managed to unblock whatever that was going on, and at least I got a crash log out of it. Sure enough, the crash logs implicate the lookupd thread that handles caches. I'm irritated that the only workaround for this is having a daemon periodically kill lookupd, but my thanks to the author for thinking of this temporary solution. Come on Apple. Fix the problem already.
Like
Version 1.0b1
Free

0.0

App requirements: 
  • PPC 32
  • Mac OS X 10.3.9 or later
Category: 
Developer Website: 
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