Documentation: podman network for DNS

dclobato commented 2 years ago

Describe the bug The location specified for 20-dns.conflist in https://github.com/boostchicken-dev/udm-utilities/blob/master/run-pihole/README.md does not work

To make the DNS network, I had to run

podman network create dns
curl -L https://github.com/boostchicken-dev/udm-utilities/raw/master/cni-plugins/20-dns.conflist -o /etc/cni/net.d/dns.conflist

The rest of instructions were fine...

UDM Information

Dream Machine Pro
UniFi OS UDM Pro 1.11.0
Controller Version 6.5.55 (Build: atag_6.5.55_16678)

Additional context Add any other context about the problem here.

boostchicken commented 2 years ago

on which file is this wrong?

dclobato commented 2 years ago

Created a pull request for this. I think it will solve #308 too...

dclobato commented 2 years ago

Done.

trnitz commented 2 years ago

This will only work until the UDM is rebooted, then the 'DNS' network will not come up.

The location of the 20-dns.conflict file needs to be in /mnt/data/podman/cni/dns.conflist, not /etc/cni/net.d/dns.conflist.

Current instructions snippet

Well, these are the current instructions that work (until reboot).

The current steps, as of today, are out of order, as covered in 308.

Download the 20-dns.conflist file to /etc/cni/net.d/dns.conflist

curl -L https://github.com/boostchicken-dev/udm-utilities/raw/master/cni-plugins/20-dns.conflist -o /etc/cni/net.d/dns.conflist

Execute the /mnt/data/on_boot.d/05-install-cni-plugins.sh script.
Create the dns network using podman network create dns

This works, until you reboot, as the /etc/cni/net.d/dns.conflist file is wiped out on reboot, and the container fails to start as the network defined in the container doesn't exist.

Correct instructions snippet

Download the 20-dns.conflist file to /mnt/data/podman/cni/dns.conflist

curl -L https://github.com/boostchicken-dev/udm-utilities/raw/master/cni-plugins/20-dns.conflist -o /mnt/data/podman/cni/dns.conflist

Execute the /mnt/data/on_boot.d/05-install-cni-plugins.sh script.
Create the dns network using podman network create dns

Explanation

The /etc/cni/net.d/dns.conflist file is just symlink to /mnt/data/podman/cni/dns.conflist

# ls -l /etc/cni/net.d/dns.conflist
lrwxrwxrwx    1 root     root            33 Feb 11 08:14 /etc/cni/net.d/dns.conflist -> /mnt/data/podman/cni/dns.conflist

In the /mnt/data/on_boot.d/05-install-cni-plugins.sh script, the variable CNI_NETD set set to /mnt/data/podman/cni, and then there is a function that creates the symlink:

populate_netd()
{
  for file in "${CNI_NETD}"/*.conflist
  do
    if [ -f "$file" ]; then
        ln -fs "$file" "/etc/cni/net.d/$(basename "$file")"
    fi
  done
}

If there the dns.conflist file doesn't exist in /mnt/data/podman/cni, then no symlink is created, and then the dns network doesn't come up on bootup.

The quick "fix" is to back out this update.

unifi-utilities / unifios-utilities