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I can't seem to figure out the problem. I've checked the deny list in CSF, and even stopped it completely, as well IPTables. Somehow I'm still blocked from accessing my server. Currently I can access it from other IPs, so I'm pretty sure that's the problem (though I could be wrong, of course. I'm no expert)

So any suggestions on what it might be, and how I could fix it, would be heavily appreciated.

I've added my own IP to the hosts.allow file, and that didn't fix it. I also added it to CSF's csf.ignore file. Again, no luck.

I'm running CentOS 5.4

All access is being blocked, I can't even get ping requests back

UPDATE: My friend suggesting pinging a different IP on the server, and it responded. So I switched the DNS to go to that IP instead, and while this is a decent bypass I'd really like to know how to fix it

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What network access service is being blocked, RDP or SSH, or ??? For that matter, what O/S is your server running? – kmarsh May 6 '10 at 12:41
One second, I'll edit my question – Rob May 6 '10 at 13:09

Use iptables -L to check the default policy of the chains as well as any rules that are in place. iptables -P will modify the default policy (you'll want ACCEPT), and iptables -F will flush all rules.

Additionally, you'll want to check /etc/hosts.allow and /etc/hosts.deny for any addresses in there that may match yours.

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Thank you for the suggestions, but still no joy. My iptables is allowing everything, and host.allow as well as hosts.deny was empty – Rob May 6 '10 at 11:47

How are you accessing your server - by name or IP?

If you are accessing by name is there an incorrect entry in /etc/hosts?

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Both. Trying to ping it, and its not responding back. Works when I use a different IP to ping it, or access it otherwise. No, /etc/hosts is fine. – Rob May 6 '10 at 17:57
up vote 0 down vote accepted

Well I went ahead and nullrouted the IP I couldn't connect to, and set the nameservers to a different IP. This solved it.

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