SOLVED NetworkManager Disable POST Install

[Nathan Martin]

I understand networkmanager is supposed to be disabled before install.

I running a hivelocity dedicated server, Centos7 WHM and started getting TONS of these errors in my

/var/log/messages:

May 11 12:00:02 server3 journal: Error while sending AddMatch() message: The connection is closed
May 11 12:00:02 server3 NetworkManager[805]: <warn>  [1526054402.0097] bus-manager: could not create org.freedesktop.DBus proxy (Error calling StartServiceByName for org.freedesktop.DBus: The connection is closed); only the private D-Bus socket will be available
May 11 12:00:05 server3 journal: Error while sending AddMatch() message: The connection is closed
May 11 12:00:05 server3 NetworkManager[805]: <warn>  [1526054405.0099] bus-manager: could not create org.freedesktop.DBus proxy (Error calling StartServiceByName for org.freedesktop.DBus: The connection is closed); only the private D-Bus socket will be available
May 11 12:00:08 server3 journal: Error while sending AddMatch() message: The connection is closed
May 11 12:00:08 server3 NetworkManager[805]: <warn>  [1526054408.0124] bus-manager: could not create org.freedesktop.DBus proxy (Error calling StartServiceByName for org.freedesktop.DBus: The connection is closed); only the private D-Bus socket will be available
May 11 12:00:11 server3 journal: Error while sending AddMatch() message: The connection is closed

My question is, disabling networkmanager at this point is want to be very sure this is the correct action to take or if there if something else going on here regarding org.freedesktop.DBus not being able to access networkmanager. This is a new error and my server is still operating as normal on the outside world.

Thank you!

 

[cPanelMichael]

Hello @Nathan Martin,

I did see a previous report where NetWorkManager lead to the error messages you provided. Uninstalling it solved the issue in that case. We document how to uninstall it at:

How to Disable Network Manager - cPanel Knowledge Base - cPanel Documentation

Thank you.

 

[Nathan Martin]

Weird, i will confirm later, but it seems a graceful reboot after latest whm update seemed to stop the errors for the time being.

 

[cPanelMichael]

Weird, i will confirm later, but it seems a graceful reboot after latest whm update seemed to stop the errors for the time being.

Hello Nathan,

The error message is likely to appear again if you leave NetworkManager installed. Here's a summary from one of our Technical Analysts in a support ticket where a similar error message was reported:

However, I did find a few upstream issues for this.

Bug 1414573 – 'systemctl restart messagebus sssd oddjobd' results in slow logins and NetworkManager errors

In general, many components don't handle restart of dbus properly, so if you try to restart the dbus daemon, you effectively would have to restart a range of service -- which amounts to a reboot.

NetworkManager doesn't support restarting dbus. Afterwards it will not reconnect to the message-bus and is effectively unreachable. When restarting dbus, you also need to restart NetworkManager.

Thank you.

 

[SactoBob]

Interestingly, this just started happening to me today too. On a server that's been up for about a year where I guess the initial cpanel install did not warn about network manager, so it wasn't turned off. A graceful reboot this afternoon also stopped all the messages and slow logins.

The below how-to is safe to do post install as well? Any issues to be expected with 200+ aliases on eth0? Will I need to do another reboot?

How to Disable Network Manager - cPanel Knowledge Base - cPanel Documentation

 

[cPanelMichael]

The below how-to is safe to do post install as well? Any issues to be expected with 200+ aliases on eth0? Will I need to do another reboot?

Hello,

You can follow those instructions post-installation, yes. You should only need to perform the steps referenced on this document. No additional steps are required, but note the following warnings:

• cPanel, Inc. does not support the Network Manager service.
• Exercise extreme caution when you disable the Network Manager. Your server may lose its network services if you do not disable Network Manager correctly.

Thank you.

 

[SactoBob]

Perfect, thank you, that's all I needed to know. I'll do these steps with a console window open via vSphere just in case.

-bob