Currently, if mDNSResponder is selected as the "mDNS service" for the OTBR build, then also Avahi gets installed - which is needed for specific CLI-invoked mDNS services that are used for testing as a reference device.
However, this special behavior (having Avahi running) is not wanted by default -- it should only be enabled when needed on the reference device. If not deliberately enabled, it should not be running because we need the reference device BR to be as much as possible equal to the non-reference-device BR build. Since the reference-build is also used as a DUT for testing the tests. Having 2 mDNS daemons on the same BR being tested does not sound like a good idea: we may get failures uniquely related to this configuration instead of the expected configuration.
Proposal: do install Avahi, but have the daemon service always be disabled by default and provide an easy way to enable it (maybe this easy way is just a "sudo systemctl start avahi-daemon" command)
Currently, if mDNSResponder is selected as the "mDNS service" for the OTBR build, then also Avahi gets installed - which is needed for specific CLI-invoked mDNS services that are used for testing as a reference device.
However, this special behavior (having Avahi running) is not wanted by default -- it should only be enabled when needed on the reference device. If not deliberately enabled, it should not be running because we need the reference device BR to be as much as possible equal to the non-reference-device BR build. Since the reference-build is also used as a DUT for testing the tests. Having 2 mDNS daemons on the same BR being tested does not sound like a good idea: we may get failures uniquely related to this configuration instead of the expected configuration.
Proposal: do install Avahi, but have the daemon service always be disabled by default and provide an easy way to enable it (maybe this easy way is just a "sudo systemctl start avahi-daemon" command)