[CentOS] 2 questions on CentOS firewall

[Timothy Murphy]

Ljubomir Ljubojevic wrote:

> ICMP packets are blocked by Billion, it's 99% chance, since public IP
> resides on the Billion. Only way (known to me) to pass ICMP to your
> CentOS server (on cheap modem/routers) is to do 1:1 NAT (all connections
> to all ports are redirected to system behind it with set IP).
> 
> If you need to be able to ping CemtOS system and not Billion, then you
> should set modem to bridge mode and pass public IP to CentOS. But caveat
> is that this would mean that if you turn on CentOS firewall or set it
> improperly you would be wide open, and that you will not be able to
> willfully bypass CentOS server (if he is down) and just plug PC's to
> modem directly.

Thanks for the response.
I don't really mind if external sites cannot ping the machine;
I was just a little surprised at this,
particularly as I didn't see anything about it in the documentation.

I'll try asking on the Billion site.

-- 
Timothy Murphy  
e-mail: gayleard /at/ eircom.net
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland