Why I cannot access specific websites?

Posts: 683  Zyxel Employee
Zyxel Certified Network Administrator - Security Zyxel Certified Network Administrator - Nebula Zyxel Certified Sales Associate 100 Answers
edited June 2024 in Networking

Scenario: There are certain websites that I cannot access, but other websites are available.

Answer: It could be ICMP TTL expired.
By default, ICSA is enabled which means the connection will terminate when ICMP is unreachable or ICMP TTL expires. So if there are too many hops, it may cause TTL to expire.

How to solve:
Disable ICSA to avoid the connection gets terminated.

Router# configure terminal
Router(config)# firewall icsa icmp-destroy-session disable

Tagged:

Welcome!

It looks like you're new here. If you want to get involved, click on this button!

Welcome!

It looks like you're new here. If you want to get involved, click on this button!