You may get an error when starting ssh on terminal,

#/etc/init.d/sshd start
touch: cannot touch `'/var/lock/subsys/sshd': No space left on device

Note:
When the sshd started through an init script a new file created in the /var/lock/subsys/  directory with the same name. Its would be /var/lock/subsys/sshd. When the service is stopped, the file will be removed from there.

Solution:

Do’nt have permission for creating files there or need to check disk space and inode space immediately.

Check Disk Space:
# df -h
File system            Size  Used Avail Use% Mounted on
/dev/sda1              15G   11G  4.2G  72% /

Check Inode Space:
# df -i
File system            Inodes   IUsed   IFree IUse% Mounted on
/dev/sda1            1923840 1923840       0  100% /

(or)

#  df -ih

 You can trace the inode usage with below command and reduce unwanted files,
 
#  echo "INODE USAGE for: $(pwd)" ; for d in `find -maxdepth 1 -type d |cut -d\/ -f2 |grep -xv . |sort`; do c=$(find $d |wc -l) ; printf "$c\t\t- $d\n" ; done ; printf "Total: \t\t$(find $(pwd) | wc -l)\n"

Sample output:
 
INODE USAGE for: /                                                                                                                                                                              
153             - bin
259             - boot
526             - dev
2641            - etc
23957           - home
11528           - lib
...
Total:          1923840     

Finally, you can start the sshd services.
 
#/etc/init.d/sshd start