DNS Cluster "Could not communicate with remote API server"

andrewmoras

Active Member
Feb 6, 2021
35
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8
Remote
cPanel Access Level
DataCenter Provider
For me the problem went away by updating cPanel/WHM initially. I'm on v98 currently and everything is working properly on both the cluster and the shared machine. I believe you've already upgraded cPanel/WHM to see if it makes a difference?

Thanks,
Andrew
 

thowden

Well-Known Member
May 17, 2013
66
7
58
Australia
cPanel Access Level
Root Administrator
Hi @cPRex

Over the last 3 months I have been working at migrating to a new infrastructure with the expectation that a 'new clean shiny' environment would be working............

Over the last few weeks I have been configuring 4 new DNS Only servers to provide my cluster and replacing the current cluster which is getting old.
@thowden - have you submitted a ticket directly to our support team so we can check this out? While I don't have any reports of that exact issue that I'm aware of, we'd be happy to take a look at things.
I logged a ticket today reference #94365981 if you want to review the gory details.

@Host1no Thanks for the api timing test !

For other interested parties, the short version is:

Old Hosting not working with error/warning in the DNS Cluster Management "Could not communicate with remote API Server".

Planning on a major migration so I ignored it and created my new shiny toys.

Started with a single CentOS server, added CPanel DNS Only and configured to taste !

Cloned server #1 out 3 more times as ns1, ns2, and ns3, keeping the source server as ns4.

And you might expect an issue might arise that affects all the servers, like they are clones, after all.

But, no. Only one server gives the API error and that is the original source server!

While I am assured that the Cluster is working and the zone copies / transfers are all ok, I hate seeing red ink on a system that is meant to be at the very core of the services we provide.

So now I will wait for a resolution.
 

DennisMidjord

Well-Known Member
Sep 27, 2016
291
52
78
Denmark
cPanel Access Level
Root Administrator
I turns out this is caused by a 7sec timeout. If your dns server does not respond to the API call within 7sec it will time out. For some reason my cPanel DNS Only servers respond way slower than our full cPanel servers, even if they have less cpu use and memory pressure. Support created this KB thats being updated regarding this issue. cPanel is investigating it in CPANEL-38426 afaik.


You can check if this is the reason by doing a
Bash:
time whmapi1 installed_versions  | tail -0
and see if it uses more than 7sec to complete. You might want to run it a couple of times to see if the real times you get is representative.
Interesting find. It's weird that DNS Only servers generally respond much slower than cPanel & WHM servers - and only sometimes. At first, the command executes in about 10 seconds on one of our DNS Only servers. If I execute it right after, it responds within 2 seconds. Do this again after a couple of minutes, and we're back to 10 seconds.
It's a few months since I was in contact with cPanel regarding the exact same issue. I'd had hoped the issue was fixed by now.
 

thowden

Well-Known Member
May 17, 2013
66
7
58
Australia
cPanel Access Level
Root Administrator
Hi All

Just to confirm that after sorting out the resolver error on one of the servers, everything has been running fine. DNS write-only from my hosting servers out to the name servers and they all respond in a timely fashion when forcing a DNS sync. So I will say my issue was simply the older servers were just that, old. They had been in place for over 3 years and with all the potential patching, updates, fiddle factor, etc. we just needed to rebuild from scratch and that was easier on shiny new toys.

Thanks for all the input.
 
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