[squid-users] wiki.squid-cache.org is broken

[Amos Jeffries]

On 2/09/2015 1:06 a.m., Yuri Voinov wrote:
> 
> Found it. My ISP can't pass ICMPv4/v6 to wiki.squid-cache.org . Here is
> problem.
> 
> # ping wiki.squid-cache.org
> no answer from wiki.squid-cache.org
> 

Perhapse that is involved. But I think you have mistaken what I wrote.

Ping just *uses* ICMP importantly it uses ICMP "echo" messages. Which
are very different beasts to the control ICMP messages. Blocking those
does not break much except tools like ping itself.


Try these three tests from your Squid machine:

## telnet 127.0.0.1 65532
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused

## telnet -4 wiki.squid-cache.org 65532
Trying 77.93.254.178...
telnet: Unable to connect to remote host: Connection refused

## telnet -6 wiki.squid-cache.org 65532
Trying 2001:4b78:2003::1...
telnet: Unable to connect to remote host: Network is unreachable


They should all return the same messages as above almost faster than you
can blink.

My above were run from a v6-enabled LAN on a v4-only ISP who blocks ping
[ICMP echo] too just like yours. The first two got to the IPv4
server/address and got a ICMPv4 port-closed error back, the third only
got to my LAN border router where the IPv6 stops and got the ICMPv6
destination-unavailable back.


You said your network is v4-only.
 => So the first and third should both return fast and at the same
speed. If either one takes a while your Squid machine is broken in
regards to the relevant protocol (v4 for test 1, v6 for test 3).

You said your ISP is blocking ping.
 => The second test should still succeed if they are blocking it
correctly. If it fails they have the broken network and maybe need
educating about ICMP.

HTH
Amos