31 January 2011

Static Routes in FreeBSD

A friend of mine recently told me that while he appreciated the detail
and content of my writings, a good deal of the subject matter was a
little beyond him.  In support of the fresh-faced sysadmins and those
that might be new to FreeBSD (we were all there once), this write up is

29 January 2011

Breaking and Syncing an MD Root Mirror

Here's one of those times where I thought, "I wonder", as in I wonder if
I can break an MD root mirror and sanely recreate it.  You can do so with
other software RAID solutions so why not here?  Well, you can.  There is
nothing short about this procedure, taking 80+ commands to accomplish.

23 January 2011

Creating an MD Root Mirror in Linux

For whatever reason, you originally set up your Linux host without a root
disk mirror and now you want it mirrored.  One could say "just re-install,"
but surely there is another way, and there is.  The solution isn't quick
or simple, though it isn't impossible.  Our host details are:

20 January 2011

Missing Linux inittab

Since I'm somewhat on a "break the boot process" kick, I've deliberately
removed '/etc/inittab' on a Linux host.  As the following illustrates,
a missing 'inittab' really isn't as bad as it seems.  Our details for
this setup are:

17 January 2011

Missing GRUB Config in Linux

Having recently written up how to restore GRUB to a missing / corrupted
master boot record (MBR)
, it seemed appropriate to follow up with
resolving a missing GRUB config file.  Our host details for this
situation are:

15 January 2011

Recreate a Linux EXT3 FS

We've looked at Solaris and FreeBSD, now it's time to look at recreating
a Linux EXT3 filesystem.  Similar to the previous two, if you customized
the options to 'mke2fs / mkfs', 'mke2fs -n' is not the answer since it
will only produce data about generic FS creation.  Our host details this

13 January 2011

Recreate a FreeBSD UFS FS

As a follow up to recreating a Solaris UFS FS, the following details
FreeBSD.  Just as with Solaris, when trying to determine how a filesystem
was created, 'newfs -N /dev/da2s1a' is not the answer, as it only produces
information relevant to a default FS creation.  Our host details for this

11 January 2011

Recreate a Solaris UFS FS

Have you ever wondered what options were used to create a UFS filesystem
(FS) on a Solaris host?  Normally when you ask that question, it
seems someone will refer you to passing '-N' to 'newfs'.  Unfortunately,
this response will only provide you with default parameters to build a

10 January 2011

Disk Cloning in Linux

A while back, I wrote up how to clone a disk in Solaris and in FreeBSD,
yet somehow managed to overlook writing up how to do so in Linux.
This write up is to rectify just that, how to clone a disk, in this case,
the root disk, in Linux.  The following are our setup details:

08 January 2011

GRUB, a Corrupted MBR, and Linux

Recently, after cloning a root disk in Linux, I ran into an issue because
I failed to setup the master boot record (MBR) on the alternate disk.
Everything else was configured, including the boot image files and grub
configuration under /boot/grub, but the MBR wasn't setup.  The following

07 January 2011

Adding Swap Space in Linux

We've discussed FreeBSD and Solaris, now it's time to have a look at
adding swap space in Linux.  As previously handled, the setting up
of swap on a free disk partition or else a swap file is discussed.
The following details our example host:

06 January 2011

Adding Swap Space in Solaris

Following up on "Adding Swap Space in FreeBSD", we take a look at the same
with Solaris.  As in the FreeBSD writeup, the usage of a free disk slice
or else a swap file is discussed.  The following details our host info:

05 January 2011

Adding Swap Space in FreeBSD

While it shouldn't occur too frequently, it is likely at some point as a
sysadmin, you will need to add additional swap space to a box.  At that
time, your options will be to use a free disk partition with suitable
space or to create a swapfile on an existing filesystem.  The following

01 January 2011

Mounting ISO Images

So you've created a fresh ISO image and now you want to use it, verify
its contents, etc.  Whatever your purpose, it is fairly trivial to
mount the image file and access it.  The following are our host details: