SOLVED Internet access lost after cPanel installation

[alfasoft]

Hello.

I installed centos 7 and then installed cpanel + whm.

I had internet connection in the server, accessed it through ssh and installed the software. After installation, I was able to access whm and login, to finish configuring the installed system. After configuration, WHM requested a reboot, I pressed the reboot button, and after the server restarted, I had no internet connectivity.

I am not able to access the server through SSH nor WHM, and from the server I am not able to ping any site. I am still able to access the server through IPMI.

I don't know if this is something installation related or where to look for any problem during the configuration process.

Any hints on how to figure this out?

Thank you.

 

[Eminds]

well .. for this issue you will need to contact your server provider , as Cpanel installation does not make any changes to your resolver files and it looks like resolver issues , did you tried with restarting the networking service on the server ?

 

[SysSachin]

Hi,
Have you installed/enable any firewall on your server ? If yes, then try to disable firewall through IPMI as might be your ISP IP or ports blocked by firewall.

 

[alfasoft]

Hello.

I followed cpanel pre installation instructions to disable selinux and network manager, and to enable network. I have also stopped iptables and cleared the rules as per the same instructions. Then I installed cPanel, and after installation I rebooted the server. I had not rebooted it in the meanwhile, so I am unsure if the internet problem was caused by those changes.

I have seen something strange when I type route -n:
Destination | Gateway | Genmask | Flags | Metric | Ref | Use | Iface
169.254.0.0 | 0.0.0.0 | 255.255.0.0 | U | 1002 | 0 | 0 | enp2s0f0

Shouldn't I see my gateway here?

I have tried adding it with `route add default gw 172.XXX.194.1 dev enp2s0f0` but I get an error:
`SIOCADDRT: Network is unreachable`

Any hints?

I am able to ping a server that is in the same network (172.XXX.194.17).

 

[alfasoft]

Hello again.

I have been able to solve the issue (at least apparently) by updating the configuration of my interface in /etc/sysconfig/network-scripts/ifcfg-enp2s0f0

I removed a few lines and added others, based on a configuration sample I found online, so I am unable to find the offending line.

Nonetheless, since I made several changes, I am afraid that it might impact cpanel or any of its features. Is there anything I can do to test the server now? Any stress tests, any commands I can run from the terminal to see if services are operating correctly (mail, mysql, http, php and or others) and if the network is how it is supposed to be?

Thank you.

 

[cPanelMichael]

Nonetheless, since I made several changes, I am afraid that it might impact cpanel or any of its features. Is there anything I can do to test the server now? Any stress tests, any commands I can run from the terminal to see if services are operating correctly (mail, mysql, http, php and or others) and if the network is how it is supposed to be?

Hello,

You can browse to the following option in Web Host Manager see the service status:

"WHM Home » Server Status » Service Status"

However, since it's a new installation with no accounts, and the previous trouble began when rebooting the system, you'd probably want to issue another reboot to make sure it works successfully this time.

Thank you.

 

[ivan.g]

I doubt the thread should have been marked as RESOLVED, since no real solution is posted.

I had the same issue, where fully working networking was lost after rebooting the server (to enable filesystem quotas).

The solution to resolve it (CentOS 7) was (as advised by cPanel support):
====================================================
I had a second look at your network configuration, and noticed that your IPADDR, GATEWAY, and PREFIX had a '0' suffix. Under NetworkManager and Networking, this should not be the case.

Please try the following steps:

1) Modify ifcfg-eth0's script file to remove the '0' suffix from those 3 lines.
2) After saving the file, restart "network" with "systemctl restart network"
3) Restart ipaliases with /scripts/restartsrv_ipaliases
=====================================================

This solution resolved my problem, hopefully it could help somebody else.

 

[benito]

Hello!

I got exactly the same problem today. A brand new VPS with fresh CENTOS 8. Installed cPanel and lost connection with server after first boot.

Ivan's fix works but after the next rebooth the 0's come back again. Im trying to figure how to permanent fix it.

 

[cPRex]

@benito - it's unlikely to be the same issues as previously mentioned in this thread since the operating systems are different now. It would be best to speak with your hosting provider to determine what configuration changes are happening.

We do mention this in our installation guide:

"On systems that run CentOS 8, the cPanel & WHM installer will automatically disable the Network Manager service and enable the network.service service."

System Requirements for CentOS | cPanel & WHM Documentation

This document describes the system requirements for your cPanel & WHM installation in a CentOS server.

docs.cpanel.net

so you may want to follow this guide before starting the installation if you are seeing problems:

How to Disable Network Manager | cPanel & WHM Documentation

This document describes how to disable the Network Manager service on systems that run CentOS 7, CloudLinux 7, Red Hat Enterprise Linux 7 (RHEL) and earlier versions.

docs.cpanel.net

 

[benito]

Hello!

This server it's on Linode. I have to disable their "auto network configuration" feature who was rewriting the zeros in ifcfg-eth0 file on every reboot.

Now the problem it's fixed.

Thanks

 

[cPRex]

Interesting - my personal server is in Linode and I don't recall having to perform that work on my end during my initial set up, although it's possible things could have changed and I only have one IP address on my machine.

 

[benito]

Interesting - my personal server is in Linode and I don't recall having to perform that work on my end during my initial set up, although it's possible things could have changed and I only have one IP address on my machine.

Yes, me too! Got several server before and no problem at all. This is the first time I see this option. Single IP too.

 

[000]

I have SAME problem with my new server.

I install more of 5 times CentOs 8 and ALWAYS after of install cPanel the server is unreachable:
no putty, no http, ANY.

I need intervention from DC for turn ON the server.

One and other time I reinstall server changing hostname, etc...

In installation number SIX I change to CentOs 7 and ALL RUN FINE, (I can connect to server after of restart).

Then:
where is the BUG ?
in current cPanel or in CentOs 8?

But most important: how fixed that?

Yet I need install CentOs 8 !!!!


Thanks

 

[cPRex]

@benito - are you saying you need to turn that option off in order for things to work well?

@000 - are those machines with issues also in a Linode environment?

 

[000]

master @cPRex my server is with OTHER ISP.

Please URGENT:

instructions to install CentOs 8 + cPanel without LOST connection when we restart.

 

[cPRex]

I don't have any specific instructions outside of what has been outlined in our installation procedures. You may need to work with that specific provider to see what is being disabled, or submit a ticket to our team so we can check the server.

 

[000]

I don't have any specific instructions outside of what has been outlined in our installation procedures. You may need to work with that specific provider to see what is being disabled, or submit a ticket to our team so we can check the server.

Thanks master, from How to Disable Network Manager | cPanel & WHM Documentation we can see:



... and what about CentOs 8 ???

 

[cPRex]

Just below that box on the same documentation page it says this:

"On systems that run CentOS 8 or AlmaLinux 8, the cPanel & WHM installer will automatically disable the Network Manager service and enable the network.service service."

so you do not need to perform any additional work in CentOS 8.

 

[000]

...you do not need to perform any additional work in CentOS 8.

Master @cPRex really one and other and other time we lost the NetWork in our server AFTER of install cPanel, please see: New Thread - after of install cPanel my CentOs don't have /etc/sysconfig/network-scripts/ifcfg-eth0 is dangerous? this is VERY confuse to us.

Again: unique "help" from DC/ISP is reinstall template of OS, they "not exists".

 

[cPRex]

If the issue is happening repeatedly only after the cPanel installation, we'd likely need a ticket to investigate that. I haven't got to the new threads yet today, but if it's the same issue it might be best to just remove the new thread to avoid confusion.