DHCP vs IPv6 address autoconfiguration

I kept on having this irritating problem. I would create a simple Gentoo network configuration in /etc/conf.d/net using DHCP for IPv4 and intending to use IPv6 address autoconfiguration.

config_eth0=( "dhcp" )

Simple and nice. The DHCP part usually worked, but IPv6 autoconfiguration didn’t. Guys on freenode’s #ipv6 IRC channel said: it should Just Work™. But it doesn’t! Well, sometimes it did. When I tried to debug it. But when I didn’t try to run tcpdump, it could just sit there for hours and not get an address. Just as if my debugging influenced it.

Interestingly, when I switched to a static IPv4 configuration, IPv6 autoconfiguration would magically start working. I haven’t worked out the root cause of this, but I’ve came up with a workaround. Well, the workaround ran into me so hard, it would be difficult not to notice. I wanted to set up VirtualBox bridged networking. When I configured it, my new bridge interface got an IPv6 address straight away, just as guys from #ipv6 would expect.

I’ve reproduced it on two machines. My working setup is the one from Gentoo’s Virtual Box howto page.

USB storage devices and gparted

USB devices like pendrives and external drives stopped mounting. I couldn’t work out what was the problem. dmesg showed that the USB device was recognized. Gnome volume manager was started. Hal and dbus also working. And my drives just wouldn’t mount automatically.

I’ve finally found a solution on forums.gentoo.org.  The problem was that gparted, which I happened to install a while ago, put this file into hal’s configuration:


I found the „true” part in the file, changed it into „false”, restarted hal, and voila, my drives are being mounted now!

Why was the file put in that place? The story is, gparted puts it there on start so usb devices don’t get in its way. It removes this file on exit. On graceful exit, that is. If it’s killed, it doesn’t remove it and the file just stays there.

Mount USB pendrive in GNOME

GNOME suddenly didn’t want to mount my USB pendrives. Dmesg said:

Unable to load NLS charset UTF8
FAT: IO charset UTF8 not found

The solution was to change NLS option in the kernel configuration. File systems -> DOS/FAT/NT Filesystems -> Default iocharset for FAT, set it to “utf8” (previously: “UTF-8”). This is a mess. UTF-8 should be always spelled as “UTF-8”, not “UTF8”, and I’m surprised that the case matters. Anyway, I’m crazy and I use Gentoo. If you want your linux to “just work”, install Ubuntu.

Gentoo installation feelings

Starting from my favorite Gentoo site, I came across this site, where I found this:

“The Gentoo install was like finding a forest, cutting down the trees, breaking a leg, getting out of the hospital, coming back, taking out the stumps and clearing the land of rocks, planting wheat, building a mill, making flower, making dough, then building an oven in which to burn it to a crisp, stealing a cow, milking it, churning the butter, picking berries, making jam. YUMMY! Breakfast is ready, but you don’t have time to eat because it’s time to update everything, including GCC, which also means a complete recompilation of everything.”

ROTFL! You’ve made a good point, to a degree. But do you know what has pushed me out of Slackware?

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CLIPS expert system for Gentoo

I’ve created an ebuild for CLIPS, the tool for building expert systems. After submitting the ebuild to the Gentoo Bugzilla, I was told it was a duplicate and I should’ve searched. Well, I did, but I only found Eclipse related bugs and couldn’t filter them out to see this sole CLIPS bug.

The previously submitted CLIPS (for version 6.21) bug is written better than mine. However, it won’t compile because they released the new version with the same file names, so it’s impossible to emerge it. I updated this ebuild and if you want to install CLIPS on Gentoo, it’s available.
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