Unable to launch noVNC

[xpillons]

Version

1.0.37

Expected Behavior

Linux Remote Desktop to connect with noVNC

Actual Behavior

Sometimes connecting to a remote Linux Desktop is failing.

Steps to Reproduce the Problem

Launch a Linux Desktop Session

[xpillons]

analysis shows that websockify failed to established a connection to noVNC using localhost.
It appears that localhost was resolved to one of the private IP of the VNET and not 127.0.0.1
This only happens when the node starts for a short period of time until the node us renamed. This is only when using azhop images captured with packer.
This line is used to decommission the waagent
/usr/sbin/waagent -force -deprovision
this in fact reset the hostname to localhost.localdomain

Azure/WALinuxAgent#2928

Azure/WALinuxAgent#2930

[xpillons]

The root cause is that the waagent when called to deprovision the VM will update the DHCP_HOSTNAME located in /etc/sysconfig/network-scripts/ifcfg-eth0 with the value localhost.localdomain. This imply that upon startup a DHCP request will be sent with the localhost.localdomain value which is wrongly registered by Azure DNS.

Workaround is to remove DHCP_HOSTNAME from /etc/sysconfig/network-scripts/ifcfg-eth0