If you get errors like this:

error: rpmdbNextIterator: skipping h#     834 Header V3 DSA signature: BAD, key ID db42a60e
error: rpmdbNextIterator: skipping h#     842 Header V3 DSA signature: BAD, key ID db42a60e
error: rpmdbNextIterator: skipping h#     850 Header V3 DSA signature: BAD, key ID db42a60e

The issue is caused by a bad GPG Key. Also note that this is a full-fledged way to rebuild the rpm database and the PubKeys.

cd /var/lib/rpm
rm __db.00[123]
mv Pubkeys Pubkeys.bad
wget http://www.redhat.com/security/db42a60e.txt
rpm --import db42a60e.txt
rpm --rebuilddb

To enable SSH on VMWare ESXi, do the following:

1. At the console, press Alt + F1
   
2. Type "unsupported" and press enter (Note, you will be doing this blindly)
3. You will be prompted for the root password, enter it.
4. vi /etc/inetd.conf
5. Go to the line for ssh (try "/ssh" to find it)
6. Uncomment the ssh line (if the cursor is over the #, hit "x")
7. Save the file ("wq!")
8. Restart the services ("/sbin/services.sh restart")

You should now be able to ssh in as root to the server.

There is a chance that you will have to restart inetd in order for this to work:

# get the PID of inetd
ps a | grep inetd
kill -HUP inetdpid

The following instructions will show you how to create either a growable (consumes space as needed) or reserved (consumes all space in the beginning) drive image file, format it, and mount it as a directory. This usable on systems that are already partitioned and you need to work with a new "partition" (say one with/without quota support), or just want a portable filesystem that you can transfer between systems.

Create a "growable" 80GB disk image called virt.img.

dd if=/dev/zero of=virt.img  bs=1M seek=81920 count=1

(note that 81920 = 80 * 1024)

or create a "reserved" 80GB disk image called virt.img

dd if=/dev/zero of=virt.img  bs=1M count=81920 seek=1

(note that 81920 = 80 * 1024)

Format your virtual partition (choose yes to continue):

/sbin/mkfs.ext3 virt.img

Mount the virtual partition:

mkdir /mnt/image
mount -o loop virt.img /mnt/image

The /etc/fstab entry (assuming virt.img is stored in the root partition "/" ):

/virt.img        /mnt/image         ext3    rw,loop,auto    0 0

If you have a server with multiple ip addresses, sendmail will default to sending email out using the first ip address.

If you want to explicitly use a different IP address, you can configure it in /etc/mail/sendmail.mc

Add the line CLIENT_OPTIONS:

CLIENT_OPTIONS(`Family=inet,Adress=1.2.3.4')dnl