Whole server blocked

[Foxie (Craig)]

I run two servers, each with its own shared IP address.

Today I noticed in MainWP that all the websites from one server won’t connect.

So I raised a Support ticket with the hosting company and wrote the following;

All of my sites on this reseller server have suddenly started refusing connections on port 443 from my management server. I suspect my management server’s IP has been blocked by the server firewall (CSF/Imunify360) or is tripping a ModSecurity rule.

Could you please check the firewall and unblock/whitelist my management server IP?

They replied;
Looking into this one, I cannot see any blocks for that IP address on either the server firewall or our hardware firewall.

I have also checked for any modsec rules that were being triggered; there are a few on the server, but none are triggered by this IP address.

So what question should I be asking to resolve this? Is this a server problem, or is it a MainWP problem?

[bojan (Bojan Katusic)]

Hey @Foxie

This sounds like a networking issue, not a MainWP-specific one.

What error message do you see in the MainWP Dashboard when you try to reconnect these sites?

@Foxie

Looking into this one, I cannot see any blocks for that IP address on either the server firewall or our hardware firewall.

See if you can find any logs with the MainWP Dashboard’s user agent: What port and User Agent does MainWP use? - MainWP Documentation

[Foxie (Craig)]

Hi Bojan,

The error message when try to reconnect is;
HTTP error - Failed to connect to barbutoconstructions.com.au port 443: Connection refused

Then everything resolved…

I think this may have been this issue;
MainWP had aggressively cached a “Connection Refused” error from a previous temporary network blip and simply refused to re-initiate the handshake