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Hi,<br><br> 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"). <br> The NAT was
configurated using the following:<br>*nat<br>-A POSTROUTING -o eth1
-j MASQUERADE<br>COMMIT<br> <br> Please, any advice
here would be
appreciated.<br><br>Thanks,<br>Patricia<br>
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<hr size=1>Abra sua conta no <a
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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 at gmail.com
On Thu, 2008-04-24 at 14:27 -0700, 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. > > What's in you /etc/hosts files? You need ip's and names in there for > clients on the Lan. You will need a primary and secondary dns > addresses in /etc/resolve.conf > > > Thanks, > Patricia > > > > > > ______________________________________________________________________ > Abra sua conta no Yahoo! Mail, o ?nico sem limite de espa?o para > armazenamento! > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos-- ~/john OpenPGP Sig:BA91F079