To improve the security of your router set an ACL to the vty lines instead of the Serial interface. And set SSH instead of telnet if you can. If somebody want to attack your device the destination IP will the same as you will set in the ACL -> so every attackers will be allowed to reach your net.
I am not sure if the original post has a typo mistake or whether it is really the config. It has this:
access-list 101 permit tcp any 192.168.1.0 0.0.0.255 established
access-list 101 deny ip any any
ip access-group 101 in
ip access-group 101 out
This has the same access list applied in and out. The only traffic which would satisfy this is traffic going to 192.168.1.0 outside and going to 192.168.1.0 inside and which is established. Nothing satisfies these conditions. So all traffic gets denied.
I suspect that the intention was to apply 101 inbound and to apply 102 outbound.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...