Ubuntu server not booting due to (possible) disk mounting problems

I have a server running Ubuntu 14.04, with one hard disk partitioned like:

sda
 sda1 -> /
 sda2 -> /var
 sda3 -> (swap)
 sda4 -> /home

Whenever I boot, I get the message The disk drive for /var is not ready yet or not present. Press S to skip, Continue to wait or M to fix manually. I get this message thrice for the mountpoints /tmp and /home as well. The big problem is that, I actually can't even press a key when it asks me to enter a key. It just goes ahead with the boot process anyways and then gets stuck at the following step:

Starting system logging daemon

Which I am assuming is because I am guessing the system logging daemon is trying to get a lock on /var/log/messages, but can't because /var isn't mounted. The problem is I can't check anything because I don't have any access to so much as a command line. I however, can get into a root prompt from the recovery mode. Which logs should I be checking for for further information and how should I basically go ahead with this?

Solution 1:

I had the same exact problem and thanks to your comment about it only happening after enabling LDAP, I was able to find out why it was happening for me. In the /etc/nsswitch.conf file, I had the following:

passwd:         ldap compat
group:          ldap compat
shadow:         ldap compat

I changed it to this and it fixed the problem:

passwd:         compat ldap
group:          compat ldap
shadow:         compat ldap

I hope this solves the issue for you as well.

Solution 2:

This sounds like for some reason Ubuntu is not aware of which disk it should really mount. Your best bet would be to find out the UUID of disk sda. You should be able to do this by running sudo blkid , which should print all disks and then check your etc/fstab to see if the UUID matches.

An example output of sudo blkid:

/dev/sda1: UUID="052f54e5-383f-4743-b3ba-fad1f0ed4ce1" TYPE="ext4" 
/dev/sdb1: UUID="18f2c5a3-0992-4c4c-a693-debd4a5b206a" TYPE="ext4" 
/dev/sdc1: UUID="0da04cdb-8307-4455-854a-2da2c4bf334e" TYPE="ext4" 
/dev/sdd1: UUID="ac5b8715-7bd4-4e1c-bd0b-82fe5383dc05" TYPE="ext4" 

Now that you have found out the UUID of sda partitions (in your case there are 4) just open fstab with your favourite editor:

sudo nano /etc/fstab

and add the corresponding entries or fix them if all are present but are showing wrong UUIDs