Category: Sysadmin

Microsoft Nomenclature

rthomson Leave a comment

My friend just linked me to an amazing example of Microsoft nomenclature that he came across while diagnosing a boot problem on his Windows 7 PC. The phrase “WTF?” comes to mind.

From http://support.microsoft.com/kb/314470:

System Volume
The system volume refers to the disk volume that contains the hardware-specific files that are needed to start Windows, such as Ntldr, Boot.ini, and Ntdetect.com.

On computers that are running the Intel x86 line of CPU processors and later versions, the system volume must be a primary volume that is marked as active. This requirement can be fulfilled on any drive on the computer that the system BIOS searches when the operating system starts.

The system volume can be the same volume as the boot volume. However, this configuration is not required.

and

Boot volume
The boot volume refers to the disk volume that contains the Windows operating system files and the supporting files. By default, the Windows operating system files are in the WINDOWS folder, and the supporting files are in the WINDOWS\System32 folder.

The boot volume can be the same volume as the system volume. However, this configuration is not required.

There is only one system volume. However, there is one boot volume for each operating system in a multiboot system.

So… the “system volume” is the volume that contains the boot files and the “boot volume” is the volume that contains the system files. It might have been opposite day when this was named. Yikes.

Thanks for the laugh, Microsoft.

Browsing Automounted NFS with Nautilus

rthomson Leave a comment

Has browsing automounted NFS shares with nautilus got you pulling out hair in frustration?

Ever since we transitioned from the RHEL4 environment to Fedora 14, people have been reporting terrible slowness and delays in nautilus when browsing our NFS shares. Reports of waiting over a minute for an NFS automount root-level directory with < 100 sub directories to display the contents are not good.

This wasn’t a problem on our old RHEL4 terminal server and I couldn’t for the life of me understand how nautilus could have become so slow in the years since RHEL4 was released. It just didn’t make sense. I started to think something had to be wrong and that this wasn’t just the new normal expected behaviour but I had nothing to go on.

I tried the basic recommendations: Disable thumbnails, disable preview, disable directory item counts. That didn’t help the user experience in any dramatic way. At this point, I started recommended pcmanfm and thunar as a way to workaround nautilus’ terrible performance. I even wrote a fairly concise script for modifying the default file manager and desktop-drawing application so that using a different file manager wouldn’t be so foreign in GNOME.

Then one day I started looking at the verbose level output from automount while browsing the NFS mounts with nautilus and found a substantial amount of this in the logs:

Apr 28 11:19:10 hostname automount[18959]: attempting to mount entry /home/.svn
Apr 28 11:19:10 hostname automount[18959]: key ".svn" not found in map source(s).
Apr 28 11:19:10 hostname automount[18959]: failed to mount /home/.svn

Oh my! Why are there repeated access attempts for “.svn”? What is causing automount to perform map lookups for “.svn” in the automount-controlled directories? Could it be nautilus?

Why yes!

As it turns out the GNOME SVN integration package “gnubversion” includes a nautilus extension and this extension was causing Nautilus to look for “.svn” directories everywhere and it just so happens that looking for “.svn” in a root-level automount directory causes slow map lookup failures that (presumably) kill the perceptible performance of browsing automounted NFS shares.

I removed gnubversion (as no one was using it) and the user experience for nautilus has normalized. While nautilus still isn’t as speedy as pcmanfm or thunar, its no longer a cause of forceful hair removal incidents… and all is well in the world.

Which Distro for PPC64 Server?

rthomson 2 Comments

We (work) have two IBM p505 Express Servers.

Right now one machine is running an old way out of support RHEL4 installation and the other is on Fedora 12, which is no longer supported by the Fedora Project. Paid support/subscription is not a consideration yet for this project, but I do want to run a modern Linux distribution for the associated modern application software and maintenance.

I basically need to move these servers to something free and supportable. I’m finding out that there aren’t a lot of options in PPC Linux as when I was last interested in this architecture. It’s pretty much just:

I realize there is RHEL and SuSE Enterprise for PPC64 but those are subscription products without free binaries available. I’m not prepared to build an RPM-based distro from source at this point so I need something with binaries or something where building from source is highly automated and integrated, such as Gentoo. Digression…

The question is which of these distros do I go with? To answer the question I suppose I need to define the roles.

These two pSeries servers a redundant pair running LDAP/Auth Service, NTP, DNS and DHCP. The load is low but I want a solid modern software platform on both these servers from now until they are replaced with in the future (which is likely to be integration into a centralized architecture).

With that said, and with my familiarity level of these distros, I would first lean towards Debian and then to Gentoo and finally to CRUX PPC.

Debian is a binary distribution, which is nice for maintaining a server. Debian is more familiar to me. What are the arguments for Gentoo or CRUX PPC?

Agree or Disagree?