Posts Tagged ‘linux’

my history of linux

November 6, 2013
  • Tried various linux distros between 1997-2003; being a mostly Windows guy back at the time (yeah I did start out as a Windows sysadmin) I ended up not investing any time trying to figure out why the mouse would not work, X didn’t start etc.
  • I ended up installing Gentoo stage 1 back in 2004. Having to manually configure pretty much everything in the system essentially forced me to learn a bunch of new stuff, allowing me to actually land a job that required Unix-fu a year later.
  • I ended up uninstalling Gentoo from my desktop system a year later when I decided that wasting 3 hours to fix my LVM setup was too much for what should be a simple emerge update.
  • In $dayjob I’ve been dutifully running, maintaining and otherwise working with a bunch of Linux systems since 2005, CentOS, Fedora, Ubuntu, RHEL 5.x and RHEL 6.x, OpenSUSE, CoreOS and maybe others I forget. Having been a mostly Solaris fanboy from 2005 onwards I have a love/hate relationship with it but I am willing to admit that it gets the job done most of the time.
  • I still think that Linux on the desktop is not worth my time and effort. If it’s worth yours then great.
  • Oh, I had an Android phone for a year or so and still love my Google gen-1 Nexus 7. Do Android devices count? 🙂

There, happy @ebalaskas?

Apparmor (synonyms: selinux, crap)

February 8, 2012

Today’s fun was with apparmor. What was a simple MySQL statement to load a bunch of data from a file to a database:


mysql> LOAD DATA INFILE '/var/tmp/some_log_file'
-> INTO TABLE entries
-> FIELDS TERMINATED BY ',';
ERROR 29 (HY000): File '/var/tmp/cosmote.ro.osn1z0.web_access.log.0.4' not found (Errcode: 13)

… was constantly failing for no good reason. It took something like 30′ of pointless online searching until it hit me:


# tail -0f /var/log/syslog
Feb 8 19:11:44 hs21-a kernel: [15359.215686] type=1400 audit(1328721104.742:113): apparmor="DENIED" operation="open" parent=1 profile="/usr/sbin/mysqld" name="/var/tmp/cosmote.ro.osn1z0.web_access.log.0.4" pid=15623 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=105 ouid=0

Well I guess it’s just like SELinux. There is a parallel universe out there where apparmor just works. Just not this one.

ARGH!

(Prev)

Selinux & POLA

July 21, 2011

Selinux is crap.Sorry redhat fun boys but its true.Not even in redhat’s documentation doesnt have enough info.

via E.Balaskas

My own experience with SELinux today? A Virtual Machine with a forgotten root password. OK, that’s easy, boot in single user mode, type passwd(1), enter the new root password, reboot. I mean the process is documented in a shitload of pages (example) and has been working like that since … I don’t know 1996? Should be a piece of cake, right?

NOOOOOOOOOOOOOOOOO!

You see this is SELinux. There are procedures to follow, “passwd root” just won’t work in single user mode and will exit immediately without a prompt. A well-defined procedure that has been working for ages is now broken. Oh well …


# echo 0 >/selinux/enforce
# passwd root
Changing password for user root.
New password:

Oh-well I am fairly certain that there is one out of more than a billion parallel universes where SELinux just works. Just one though.

References: POLA

The truth about (Solaris and) Xen

July 8, 2010

Why is Solaris not good enough to act as a hypervisor requiring Sun to ship Xen in xVM?

via Tales of a Code Monkey

Because what used to be Sun didn’t suffer from the NIH syndrome that seems to haunt Linux developers. And while Linux may one day dominate everything, this doesn’t necessarily mean that it’s the best thing since sliced bread the same way that x86 is not. It will just mean that the market dynamics would have won.

Till then I am thankful that contrary to RedHat some people still appreciate that KVM is an emerging technology and Xen the leading FOSS virtualization solution. Thanks to them I can happily type uptime:

# cat /etc/release
Solaris 10 10/09 s10x_u8wos_08a X86
Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
Use is subject to license terms.
Assembled 16 September 2009
# uptime
9:46pm up 1:10, 1 user, load average: 1.14, 1.98, 2.19

and get consistently low load average utilization in my Solaris VM rather than in excess of 15, like I did with KVM.

Tip of the day: don’t install Squeeze with LVM

July 5, 2010

Not unless you want to lose quite a lot of time. Seems like they still need to iron out quite a few things when it comes to supporting something more complicated than a simple partitioning scheme.