Wednesday, October 07, 2009

Tuesday, September 22, 2009

DHCP Usage

I don't think anybody reads this blog, but...

If anybody is reading (Hello? Is this thing on?) I have a question... How extensive is your use of DHCP? I'm slowly migrating almost every network device to statically assigned DHCP, including servers. Do you use DHCP for servers and other fixed devices?

Just wonderin'...

Wednesday, September 09, 2009

Upgrading RHEL from 5.3 to 5.4

I was having all sorts of strange problems while upgrading my test box from RHEL5.3 to RHEL5.4.  I did a search, but it didn't seem to turn up much... just a link to an unrelated problem, and a Russian website.  Well, I don't know Russian but I was able to decipher a hint: "yum clean all".  That did the trick.  I think I'll run that prior to upgrading all my production boxes.  Here's the error I was getting:

# yum update libX11
Loaded plugins: rhnplugin, security
Skipping security plugin, no data
Setting up Update Process
Resolving Dependencies
Skipping security plugin, no data
--> Running transaction check
--> Processing Dependency: libX11 = 1.0.3-9.el5 for package: libX11-devel
---> Package libX11.i386 0:1.0.3-11.el5 set to be updated
--> Running transaction check
---> Package libX11-devel.i386 0:1.0.3-11.el5 set to be updated
--> Processing Dependency: /usr/share/X11/XKeysymDB for package: openmotif22
--> Processing Dependency: /usr/share/X11/XKeysymDB for package: openmotif
--> Finished Dependency Resolution
openmotif22-2.2.3-18.i386 from installed has depsolving problems
  --> Missing Dependency: /usr/share/X11/XKeysymDB is needed by package openmotif22-2.2.3-18.i386 (installed)
openmotif-2.3.1-2.el5.i386 from installed has depsolving problems
  --> Missing Dependency: /usr/share/X11/XKeysymDB is needed by package openmotif-2.3.1-2.el5.i386 (installed)
Error: Missing Dependency: /usr/share/X11/XKeysymDB is needed by package openmotif22-2.2.3-18.i386 (installed)
Error: Missing Dependency: /usr/share/X11/XKeysymDB is needed by package openmotif-2.3.1-2.el5.i386 (installed)
 You could try using --skip-broken to work around the problem
 You could try running: package-cleanup --problems
                        package-cleanup --dupes
                        rpm -Va --nofiles --nodigest

Wednesday, August 19, 2009

Focus

It's nice to be able to dive into a project and not have emergencies that need to be dealt with.  I've made a lot of headway into setting up my Bcfg2 repository.  But when you start to surface, you realize that all those items in your inbox still need to be taken care of, even if they're not emergencies.  There's a lot of 'em...

Wednesday, June 24, 2009

How to Find Dangling Symlinks

Sometimes, you need to find all symbolic links which point to a non-existant target (aka, a dangling symlink).  Well, I found[1] an easy way to dig them up...
find -L . -type l
And the best part is, it's portable (well, it works on RHEL5, Ubuntu 6.06, and Mac OS X 10.5).  Another way[2] to do it with GNU find is...
find . -follow -lname '*'
[1] http://linux.derkeiler.com/Mailing-Lists/Debian/2006-06/msg01907.html
[2] http://mail.milwaukeelug.org/wws/arc/mlug-list/2007-03/msg00243.html

Wednesday, June 17, 2009

RHEL5 and Firewire

It took a while, but I finally figured out how to fully enable firewire in RHEL5.3.

Because firewire is still a "Technology Preview" in RHEL5.3, you must disable the blacklisting of the kernel module in /etc/modprobe.d/blacklist-firewire
# Comment out the next line to enable the firewire drivers
#blacklist firewire-ohci
But that's not all you have to do... Oh no... In order for the drive to be visible in your file manager (we use Xfce, but it also applies to Gnome), you must also mark the drive as "hotpluggable" in HAL. Why it isn't done so automatically, I don't know.

Create or update the file /etc/hal/fdi/policy/preferences.fdi with this code:
<?xml version="1.0" encoding="UTF-8"?> <!-- -*- SGML -*- -->
<deviceinfo version="0.2">
<device>
<match key="@info.parent:@info.parent:@info.parent:info.linux.driver" string="firewire_ohci">
<match key="info.category" string="storage">
<match key="storage.drive_type" string="disk">
<merge key="storage.hotpluggable" type="bool">true</merge>
</match>
</match>
</match>
</device>
</deviceinfo>
Now, I don't know if that's the best matching, but it works.