The error message I am seeing is:
Failed publickey for raj from 10.*.*.** port 34355 ssh2 Mar 18 05:22:34 unixbuild sshd: [ID 1000034 auth.info] Failed password for raj from 10.*.*.* port 34355 ssh2
the user Raj has tried to connect from IP address 10...* You cannot see from this what application is connecting but you can identify the machine.
If you do not already know what machine holds this IP address you can trace it via IP address or MAC (arp -an)
You can also prevent access from this machine and see what breaks. You can prevent access either via iptables or more simply use
route add 10...* reject
this will reject all traffic to this host so it cannot talk to the unixbuild server