This is a quick write-up on an error I’ve been having with my MacBook and a drive connected to Airport Extreme. It’s really only here so that Google will index it and the info will hopefully be one step in a solution for others with the same problem.
The issue is with my Free Agent drive when connected to an Airport Extreme via USB and accessed with my MacBook Pro, running Snow Leopard, using an AFP connection. I used this drive for a while with no problems in Leopard, and then did a clean install to Snow Leopard without any problems. One day, I tried to access my drive and got the following error:
The server “MettaFi” is available on your computer. Access the volumes and files locally.
Geeks: This post, like all of my posts, is not written from a strictly technical perspective. Thus it has a “beat around the bush part” and a “get to the point” part– or as close to a “get to the point” part as I’ll ever get. You might want to skip to the latter.
Non-geeks: This will probably not be interesting to you in the least.
The “Beat Around The Bush” Part
Now, this is obviously a problem, since the “server” is my network drive, and that’s in another room in the house connected to my wireless router. I couldn’t figure out what the hell would be meant by “access the volumes and files locally” except that Snow Leopard somehow thought that this drive was physically connected to my computer.
This error has been going on for a few days, and I’ve been getting increasingly frustrated. This morning, I tried once more to figure it out and magically, it Just Worked. Now, if there’s one thing a programmer hates more than an undefinable computer problem, it’s an undefinable computer problem that goes away for an undefinable reason. That’s random, and randomness is scary in computers.
Then, after about five minutes using my strangely back from the otherworld drive I got the problem again! Now, if there’s anything a programmer hates more than an undefinable computer problem that goes away for an undefinable reason, it’s–
You get the picture. Mystery is a good thing to have in real life, and in literature, and in romance… it’s a very, very bad thing to have with computers. In a computer’s brain, mystery is that place between 0 and 1, and that undefined land is dangerous.
After asking the all-knowing interwebs, I began to piece together some evidence that might lead to a solution. This seems to be working so far for me, but since it’s an undefinable problem that previously disappeared and reappeared seemingly without my involvement, the mystery is still unsolved.
The “Get To The Point” Part
Replaying the actions that led to this situation, the primary one seems to be my using an iTunes library that was hosted on the networked drive. I did this, not by using the iTunes Preferences pane and choosing a new “iTunes Media Folder Location,” but by starting iTunes while holding the option key and creating a new library on the networked drive. This library was automatically named “iTunes 1″ (this becomes important later).
Since I almost exclusively sleep my MacBook Pro, rather than shut it down, I had constant problems with iTunes when moving locations. iTunes would frequently freeze when I started working in another location (because the library that it was “currently” connected to was suddenly missing). I eventually had to create a local iTunes directory in my home folder to use while traveling. This was beginning to bug me, so I resolved to change my music setup such that I used the “iTunes Media Folder Location” strategy.
Interestingly, my plan was to do that this morning, when this problem reoccurred.
AFP Connection Problems In Snow Leopard?
The connection to my drive is made through an AFP connection automatically by Snow Leopard. As noted by 4lex on Twitter, many other people have had this same, or a similar, problem after upgrading to Snow Leopard (scary thought). Apart from the Twitter traffic, there is an Apple Discussion Forum entry as well as others12. Furthermore, it seems that the problem is not something that the normal support line can deal with, as others have been forwarded to engineering.3
One thread I saw on the Apple Discussion forum noted that a fix was supposed to be rolled out in the next major update: 10.6.2, but I didn’t want to hold my breath.
A Possible Alias Problem- or Just A Bug That Was Fixed?
While searching, I found an old post about Mac Classic apps run on OS 9 that seemed oddly appropriate. The post talked about having an alias to a server or file left over on your computer. Put simply, if that alias is still live, and the computer tries to access the original file using another alias, there’s a bit of a collision.
I didn’t know where this alias would be, so I cleaned up my “recent servers” and “recent files” to see if that fixed it. Nothing.
So I cleaned out my trash. Nothing. Finally, I thought about my iTunes problems and looked in my local iTunes directory. I saw a folder called “iTunes 1″ in that directory. Now, this is possibly a coincidence. In fact, it’s probable that iTunes created this during one of the times I traveled and iTunes froze. However, it’s at least somewhat likely that this directory was some sort of alias to the “iTunes 1″ directory on my networked drive. Taking a chance, I deleted it. Before deleting, I check the media folder to see if any music had to be moved, but it was empty.
Once I deleted the phantom iTunes 1, I checked for system upgrades to Snow Leopard (there were some). That check caused me to restart. After restarting, everything seems to be working. The problem with this, of course, is that I don’t know if it’s the Apple Updates or the filesystem alias that fixed the problem. More hanging out in that place between 0 and 1.
Meanwhile, back at the ranch:
I love The TwitterWebs! Just as I was proof-reading this, 4lex sent me a tweet about his problem that seemed to suggest that the alias thread might be a key piece of information. It seems to me that if 4lex renamed his router and his MacBook Pro in the Sharing PrefPane, all the aliases that were sitting on his drive would be broken and Snow Leopard would create new ones. Thus, the collisions would go away. Again, this is not confirmed, but more evidence to that as the source of the problem.
Your mileage will vary, but I hope this information helps lead others toward a solution. If I have any further problems, I’ll give an update in the comments, so subscribe to them if you’re interested in any further developments.