There's a mobile version of our website.
As we know, port 161/162/1993 could be TCP or UDP and snmp traps are sent out in UDP. Could you please tell me when TCP 161/162/1993 will be used and how to identify it is TCP or UDP on a Cisco router? Thanks very much!
As of version 11.x of IOS, Cisco no longer uses
port 1993. If you are on a version of IOS that
is below 11.x, you are not Y2K compliant.
By default, SNMP uses UDP, not TCP. Polling
(sent by servers) goes to port 161. Traps (sent
by agents) go to port 162.
As I know UDP 161/162 are used for SNMP. On my network a monitor only these two ports concerning the SNMP. If you want to verify if it is udp or tcp you can do it very easily with an access list. For example:
access-list 166 permit icmp any any echo
access-list 166 permit icmp any any echo-reply
access-list 166 permit udp any any log
access-list 166 permit tcp x.x.x.x x.x.x.x any log
access-list 166 permit tcp any x.x.x.x x.x.x.x log
access-list 166 permit ip any x.x.x.x x.x.x.x
access-list 166 permit ip any any
You can even simplyfy this list by using any any for the tcp and fot the ip part.
This way you won't affect your regular communication and you'll be able to view the log messages on the console or terminal.
Login to share your discussion activity with your friends on Facebook. You can control what you share and turn off sharing anytime.
Your Facebook friends can now see that you have started this discussion
Your Facebook friends can now see that you have commented on this discussion
Your Facebook friends can now see that you have read this discussion