So we've been trying to set up an LDAP sync with an outside vendor. We have a Cisco ASA, which I'm fairly confident is configured correctly as far as NAT/PAT goes. I also opened the ports on the server itself. So here is my question, which may be incredibly stupid….but I'm more of a networking guy so I could definitely use some help:
The outside vendor is using telnet to test the port (ex: telnet myip 636/389)
Do I need to have the telnet client running on the server for this to connect? The particular server they are trying to connect to does not have the telnet service running (it errors out when started, I haven't had a chance to really look at it). I've looked over the configs a bunch of times so now I'm wondering if something to small could be the reason their connection testing is failing. Again, I apologize if it's a stupid question, but I appreciate the help.
Ldap – Third party trying to test LDAP(s) port on our server
ldaptelnet
Best Answer
You can test some service with telnet, as it handle the connection handshake correctly, you don't need anything on your side. I do it a lot with mail server to test the SMTP. (telnet ip 25 can test if the remote smtp server answer)
For your question for LDAP, the telnet prompt should turn all blank if the remote LDAP server answer, but the remote tester can't do much than that as each message are in binary, so he can't easily simulate a conversation over telnet. (some reference; https://stackoverflow.com/questions/11549731/is-it-possible-to-send-ldap-requests-via-telnet)
It allow your tester to simply test if the service answer (and that the routing is correct, as if it dont answer in telnet, it will not answer any other way)