Category: Geekery

OpenID weirdness

For some strange reason, when some people post comments to my blog using their livejournal OpenID (jenniferm and ptomblin_lj, for instance), SpamKarma2 complains that their posts are missing the “payload”, which is a hidden input field with a cryptographic hash of some of the other values in the form. But others can post without this problem. I look at the page source before I post, and I can see the payload is there, so something is stripping it. I have no idea if this is some sort of interaction with Akismet or a bug in OpenID or what.

So far I’m not impressed with Akismet. Ever since I’ve installed it I’ve seen an increase in false positives. I’m going to try to disable it and see if the OpenID commenting problem goes away.

Update: Disabling Aksimet didn’t help. Must be the OpenID plugin.

What’s wrong with USB 2 on my home machine?

I have a PCI USB 2 card, which I use to plug in external USB 2 hard disks for backup. I have one external disk that I’ve been using for months now, and it’s been working fine. Some months ago I bought a second drive, with the intention of swapping between the two, and keeping one in my desk at work as an off-site backup. It worked for a while, but then started failing during backups. I’d lost the reciept, so I ended up selling it locally to somebody under the understanding that it may fail, and if they don’t like it they can return it.

The day before yesterday, I bought a new drive to try again. I stuck it in and backed up about 200Gb to it. Then I simulated 7 nightly backups all without incident. Last night, our power glitched for about 3 seconds, which was long enough to knock both the external drives off, because they’re not on the UPS. This morning I power cycled them and mounted them both, and did another nightly backup. But in the middle of backing up to the second drive, it started failing in a very similar way to the old drive. It started with:

Mar 15 07:51:30 allhats kernel: lost page write due to I/O error on sdb1
Mar 15 07:51:30 allhats kernel: sd 18:0:0:0: rejecting I/O to device being removed
Mar 15 07:51:30 allhats last message repeated 47 times
Mar 15 07:51:30 allhats kernel: sd 18:0:0:0: rejed 18:0:0:0: rejecting I/O to device be
ing removed
Mar 15 07:51:30 allhats kernel: sd 18:0:0:0: rejecting I/O to device being removed
Mar 15 07:51:30 allhats last message repeated 1154 times
Mar 15 07:51:30 allhats kernel: __journal_remove_journal_head: freeing b_frozen_data
Mar 15 07:51:30 allhats kernel: EXT3-fs error (device sdb1): ext3_get_inode_loc: unable
to read inode block - inode=7897505, block=15794191
Mar 15 07:51:30 allhats kernel: journal commit I/O error

Two external hard drives, both of which caused these sorts of problems under load. Hmmm. I’m starting to wonder if it’s not the disks. Maybe it’s something about the USB controller. I need to test this somehow. I wonder if my work computer has USB 2?

And this morning’s lessons are…

  • If you’re about to start something dangerous (like an aptitude upgrade on your dom0), and you set up an at job to reboot it if it causes the box to lose network connectivity, don’t forget to atrm it if everything is fine afterwards.
  • reboot in an at job doesn’t do the right thing – my box was still responding to pings but I couldn’t get to it at all. Next time try shutdown -r now

OpenID is a go, it appears

Last night I had an idea. And typically for me, I couldn’t sleep properly as I kept trying to remind myself about the idea. I should have gotten up and tried it, but if it hadn’t worked I would have gotten even less sleep.

Anyway, the problem I was having with the OpenID plugin is that I forgot to make the plugin’s temp directory group writable. Most people seem to be ok with just making all their blog files writable by the web server, but I worry about the number of security holes that seem to pervade PHP applications so I make all the WordPress files belong to the user “blog” and only the ones that the web server has a legitimate reason to write belong to the group “www-data” and are group-write. When I installed this plugin, I made the tmp directory belong to the group “www-data”, but I forgot to “chmod g+rwx” on it. Duh. Even more “duh” worthy, I see that the plugin page has a FAQ that has that as item 1.

It seems to be working now. Let me know if you can’t comment.

No OpenID, I’m afraid

I tried to install this OpenID Comments for WordPress plugin. My luck with with WordPress plugins is about 50% success, and most of the ones that fail seem to be ones suggested by Jen. Or at least my biggest other failures have been with various plugins that attempted to embed my Gallery, and Jen seemed to have no trouble with hers. (I got it to the point where it was throwing off “duplicate primary key” errors, but no closer.)

This time, it looks like it would go off to LiveJournal, get successfully authenticated, but when it came back instead of putting the comment on the post it was posted to, it was putting it on the same non-existent blog URL as in the “-1 comments” debacle. The “-1 comments” thing was caused because LJXP was sending off the entry to LiveJournal before the comment number plugin knew what postid it was, but I hacked the code of both plugins and made it work. This time I looked for something obvious, but with no luck.

Maybe somebody can suggest an OpenID WordPress plugin that works?