Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

HELP! Can't Telnet from inside to 891

I have a 891 router I have been testing some things on. I have been able to successfully telnet to it in the past with no problems. Just yesterday I was trying to set an interface to have an IP of 10.10.10.2 which I realized was an IP I had forgot to exlcude from DHCP and it was handed out to the computer I was using to telnet in. So I wrote in the exlcude commands and did an ipconfig -release ipconfig -renew on my PC that had the 10.10.10.2 IP. After the renew I was given 10.10.10.7 (put in a few more excludes).

However the release dropped my telnet connection and afterwards I was completely unable to telnet in, getting the error that says I cannot open the connection on port 23. I had made some changes to my entire config beforehand which had it switch to use a new public IP. I never saved the changes and did a hard reset by unplugging the router to get my old config back and see if I could telnet after that. Still could not get in, same error. Well I went through and remade my entire config to use the new public IP. My 10.10.10.7 PC can access the internet, DNS, ping the router, all just fine. Still can't telnet. I remade my line/vty config and made sure it matched up with a config I had on another router. Still can't telnet.

Last thing I did was go in and manually clear all open line connections. All that is left is an idle 0 con 0 line that it wont let me close. Still can't telnet.

What the hell is going on with this thing? I am completely at a loss to explain why I cant telnet. It must be something in my ACLs that I am misisng? Please help, I was just about to move this to an environment where I HAVE to access it by telnet!

EDIT: attached config

2 REPLIES
Hall of Fame Super Silver

Re: HELP! Can't Telnet from inside to 891

Hmm,

your vty lines are controlled with an access-list:

line vty 0 4

access-class 23 in

access-list 23 permit 10.10.10.0 0.0.0.7

I believe that access-list will allow clients from 10.10.10.1-10.10.10.6. Try lifting it for a moment (or making the inverse mask 0.0.0.15) to open up telnet to a few more hosts (or make it a set of /32s).

New Member

Re: HELP! Can't Telnet from inside to 891

I actually did figure this out on my own. I am wondering why I was able to telnet in with no problem before without the access-list and I am also wondering why my other router, a 1921, also does not have the access-list but I am able to telnet with no problems.

948
Views
0
Helpful
2
Replies
CreatePlease login to create content