Re: DNS problem (on NAT configuration)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]



Patricia Bittencourt wrote:

   Hi,

I'm dealing with a problem that the worker nodes that are behind a NAT aren't able to reach outside from time to time. (ie: on a given moment I can ping an address name and immediately after I cannot: "ping: unknown host").
        The NAT was configurated using the following:
*nat
-A POSTROUTING -o eth1 -j MASQUERADE
COMMIT
Please, any advice here would be appreciated.


The obvious fix is to configure your NAT gateway host as a caching DNS server and make the hosts behind NAT use it's private address instead of something on the other side. However, it should work anyway. Do you have enough traffic that you could be filling your conntrack tables? UDP entries remain for a timeout interval since you can't see a disconnect.

See if the /proc/sys/net/ipv4/netfilter/ip_conntrack_* values are reaonable for your scale.

--
  Les Mikesell
   lesmikesell@xxxxxxxxx
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
http://lists.centos.org/mailman/listinfo/centos

[Index of Archives]     [CentOS]     [CentOS Announce]     [CentOS Development]     [CentOS ARM Devel]     [CentOS Docs]     [CentOS Virtualization]     [Carrier Grade Linux]     [Linux Media]     [Asterisk]     [DCCP]     [Netdev]     [Xorg]     [Linux USB]
  Powered by Linux