FIX_SLOW_BOOT.md

I was wondering why it took so long for my deep learning rig to fully boot up. It literally takes 5 minutes to go from reboot to ssh service start. Unlike desktop motherboards, the ROMED8-2T has two 10G RDMA ethernet controllers and a port for the IPMI interface.

For a while I thought I must have done something wrong - but it turns out when there are free, unmapped ports it will block boot. To fix this, you just need to make the other interfaces optional in your /etc/netplan/*.yaml

network:
  ethernets:
    enoXnpX:
      addresses:
      - ...
      nameservers:
        addresses:
        - ...
        search: []
      routes:
      - to: default
        via: ...
    enoXnpX:
      dhcp4: true
    enXXX:
      dhcp4: true
      optional: true
  version: 2

Finally, restart and all will be right in this world.

sudo netplan generate
sudo netplan apply
sudo reboot

For debugging in Ubuntu

ip a
cat /etc/netplan/*.yaml
sudo lshw -class network