Snap 1052 cannot bind DHCP to network interface

[marxjohnson]

Issue Details

• Version of AdGuard Home server:
  • 0.104.0
• How did you setup DNS configuration:
  • System
• Operating system and version:
  • Ubuntu 18.04.5

Expected Behavior

Before the snap refreshed (snap rev 606/adguard version 0.103.3), DHCP was enabled and working. After it updated, I expected it to continue working.

Actual Behavior

DHCP stopped working after the refresh. Attempting to disable and re-enable the service resulted in the following error:
Error: control/dhcp/set_config | Failed to start DHCP server: cannot bind to interface enp3s0: operation not permitted | 400

[marxjohnson]

As a workaround until a fix is published, running snap revert adguard-home restored the previous version.

[Tloram]

Same issue here. DHCP stopped working over night when the snap updated to 0.104

Network is now down. Oh dear.

[ameshkov]

We're looking into it, don't worry.

Meanwhile, could you please post the dhcp: section of your config files? (AdGuardHome.yaml)

[marxjohnson]

Here is the dchp section of mine:
Snap rev 606 (working):

dhcp:
  enabled: true
  interface_name: enp3s0
  gateway_ip: 192.168.0.1
  subnet_mask: 255.255.255.0
  range_start: 192.168.0.50
  range_end: 192.168.0.150
  lease_duration: 86400
  icmp_timeout_msec: 1000

Snap rev 1052 (not working):

dhcp:
  enabled: true
  interface_name: enp3s0
  dhcpv4:
    gateway_ip: 192.168.0.1
    subnet_mask: 255.255.255.0
    range_start: 192.168.0.50
    range_end: 192.168.0.150
    lease_duration: 86400
    icmp_timeout_msec: 1000
    options: []
  dhcpv6:
    range_start: ""
    lease_duration: 86400
    ra_slaac_only: false
    ra_allow_slaac: false

[ainar-g]

Good day, @marxjohnson! Thank you for the report. I was able to reproduce the bug. Apparently, the new way we filter packets to only get the ones from the required interface on Linux requires more permissions than before. We're investigating how to fix this.

[ameshkov]

@marxjohnson @Tloram please try installing AGH snap from the edge channel, the issue should be gone now.

snap refresh adguard-home --channel edge

[marxjohnson]

Hi @ameshkov, I just tried that:
adguard-home (edge) v0.104.0-SNAPSHOT-9761f133 from AdGuard (ameshkov✓) refreshed
Unfortunately, the problem still persists.

[ameshkov]

Weird, we'll double-check.