I have the following situation internet internet | | | | mail server ----------- firewall (10.21.23.20) (10.21.23.21) | | intranet (192.168.x.x) The firewall is also a caching DNS, to speed up lookups and overcome DNS server downtime. My problem is that when I lookup the mail server the address I receive from 10.21.23.21 is the external address, as seen from outside. I would like the address to be solved for internal machines as the shortcut 10.21.23.20. The routes are correct according to traceroute. I thought that if I modified the firewall's /etc/hosts including the address of the mail server as 10.21.23.20 and setting nsswitch.conf to hosts: files dns would make it work, but they cached address seems to have priority. I also restarted named, but the situation remains. What should be the correct configuration? Thank you, Gerardo Searching for the best free email? Try MetaCrawler Mail, from the #1 metasearch service on the Web, http://www.metacrawler.com - : send the line "unsubscribe linux-admin" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html