I am having a problem with one of my servers not registering.

Here is what it look like

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server8*CLI> iax2 show registry
Host dnsmgr Username Perceived Refresh State
67.215.233.178:4569 N 27723 <Unregistered> 60 Request Sent
67.215.233.178:4569 N 27722 <Unregistered> 60 Request Sent
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server8*CLI> iax2 show registry
Host dnsmgr Username Perceived Refresh State
67.215.233.178:4569 N 27723 <Unregistered> 60 Timeout
67.215.233.178:4569 N 27722 <Unregistered> 60 Timeout
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I can icmp ping 67.215.233.178 and I can connect to it's ftp port but the allstarlink registration fails.
This server did work in the past and nothing in any of the .conf files has changed since it was working last.

I have rebooted everything many times while troubleshooting this. This is an ACID install from a few years ago, last updated Nov 2013, the same as my other 2 servers that are still working fine.

I don't really know when the problem started but I know it has been more than a couple of days.

Can anyone suggest next steps in troubleshooting this problem?

Chuck WB9UUS.