remote login

[haeman]

I have a two unix server ( serverA and serverB ) , I checked that a login in serverA ( who -u |grep pts/30) , this pts is from serverB (by telnet) , if I want to know which user (IP address) in serverB use the login ID "ora_usr" to login serverA , what can i do ? thx

serverA
======
#who -u |grep pts/30
ora_usr pts/30 Apr 29 11:45 serverB

[Ramesh S · Accepted solution]

Hi

"ora_usr" from serverB has logged in serverA.

Oracle must be using the "ora_usr" id. Have a look on /etc/passwd file.

Best Regards,
Ramesh

[Jeeshan]

#who -a|grep

[haeman]

thx replies,

ora_usr is common user , so I don't know which user use this login at the time .

thx

[Ramesh S]

HI

In that case, do "last -R" to know the IP address from that user logged in.

Best Regards,
Ramesh

[haeman]

thx Ramesh S

I think the last -R in serverB only show who is logging in serverB , but can't show who is using telnet to connect serverA , for example , there are 10 user use ora_usr to telnet to serverA , how do I know who is who ? thx

[Ramesh S]

Hi

I guess, You can only see the IP address/system name only from where user id 'ora_usr' logged in.

Best Regards,
Ramesh

[OFC_EDM]

Unfortunately I don't have lsof on my system so I can't check.

But lsof which lists open files "might" have information to help find out who has a telnet session open.

lsof gives an understanding of the relationship of processes to open files descriptor and sockets and much more.

May be worth a shot looking at it.

If I get a chance I'll install it and see if it will be of any use.

[OFC_EDM]

I did find this post from someone who was trying to find the IP on the other end of a Telnet session.

"On Unix one may use 'lsof' (if available) and grep on the shell pid and
file descriptor 0 to find the line containing the source ip addr. In
some flavors of Unix the /proc filesystem can also be of help."

Sounds like lsof may be of help after all.

[OFC_EDM]

or try

who -mu

That command showed my machine name including domain for my ssh session.

Which I then used nslookup to get the IP.

I think it would work for telnet too.

[haeman]

thx reply ,

the lsof can show the remote IP , but how to know which user ( from 10 of them ) is this login session ?

for nslookup , you mean run it at serverB ? I tried to use nsloopup IP but not work, can advise how to use it ? thx

#man nslookup
nslookup -query=hinfo -timeout=10