Ip aliasing error?

[Carlos <cayoxxx@gmail.com>]

Hello List:

 Sorry my English. I have a firewall with a debian Woody installed
with a kernel 2.4.29.  This it connected to internet trought  HDSL
line  with a  Cisco router  1721 , bridge mode. Has configured 5
public ips by ip aliasing. The firewall works correctly although
before  4 or 5 days one of the ips they configured is not accessible
from internet. Since inside of the network  responds correctly.  If
ifdown and ifup  the interface  does not fix anything.  If I configure
some host inside of the network with that Ip, is accessible from
Internet. Finally if I powerOff the router and powerOn again, all
correctly. Any suggestion?

Thanks.

Carlos