Long story short: I use VMware and I use Ubuntu. With Ubuntu 16.04 everything worked nicely out of the box. With Ubuntu 18.04 it doesn’t. I finally got tired of manually setting my hostname and network settings every time I need a new server, and decided to fix my template once and for all.
The first thing that doesn’t work – as mentioned in an earlier post – is deploy-time configuration of the network based on vCenter templates.
For some weird reason, Ubuntu has chosen to entirely replace the old ifupdown system for configuring the network with a combination of Cloud-init and Netplan. If we choose to download the installation image with the traditional installer, at least we don’t get cloud-init, but Netplan remains.
According to the Netplan FAQ, we can install Ubuntu Server without using Netplan by pressing F6 followed by ‘e’ in the installer boot menu, and adding
netcfg/do_not_use_netplan=true to the preseed command line.
Unfortunately this leaves us with a disconnected machine after first boot: It turns out Ubuntu isn’t smart enough to actually install ifupdown if netplan is deselected – at least not using the current installer, 18.04.01.
The working way
The solution to the problem above is still (in February 2019) to perform a clean install with Netplan, and then manually remove open-vm-tools and replace it with VMware’s official tools, since open-vm-tools do not yet support Ubuntu’s weirdness even 10 months after 18.04 was released.
The default DHCP behavior in Ubuntu 18.04 is nothing other than idiotic for use in VMware templates: Despite newly deployed machines naturally getting new MAC addresses, they insist on asking to be handed the same IP address as their template, and they naturally don’t understand if the lease is already taken but will keep stealing the IP address from each other.
Fortunately, according to this post over at superuser.com, there’s a way to fix this. Edit
/etc/netplan/01-netcfg.yaml, and tell Netplan to use the MAC address as the DHCP identifier, like this:
dhcp4: yes dhcp-identifier: mac
After this, new machines deployed from the template should behave slightly more sanely.
Painfully long Grub menu timeout
Grub’s boot menu has a default timeout of 30 seconds in Ubuntu 18.04. The relevant setting is apparently modifiable in
/etc/default/grub. Only it isn’t. The default value for
GRUB_TIMEOUT is 2 seconds, which it doesn’t adhere to at all. Logically (no, not at all), the “fix” is to add the following line to
update-grub with superuser rights, and reboot the computer to confirm it worked as intended.
With the changes detailed above, and after installing Python to allow Ansible to perform its magic on VMs deployed from this template, I finally have reached feature parity with my Ubuntu 16.04 template.