moOde sometimes shows up LAN as <hostname>-2.local

[TheOldPresbyope]

I'm sure I'm in a small minority with my LAN setup. My ISP-provided cable modem/router/AP does not resolve DNS requests for local hosts so on the LAN I use multicast DNS (e.g., the pseudo-domain .local) exclusively.

Normally, this causes only one headache with moOde. When I use the webUI to scan the LAN for NAS shares, I have to remember to hand-edit .local into the results so that the subsequent mount command will succeed. Otherwise it fails, indicating the host was not found. [1]

However, from time to time I get a curious result when I reboot a moOde host (happens a lot in testing). The host starts getting advertised in the pseudo-domain with a suffix, typically, "-2", appended. Example, host "moode" becomes host "moode-2". This is annoying [2] because anything already configured to deal with, say, moode.local then has to be changed to moode-2.local.

After some digging around the InterWeb™ I found a useful post which suggested this problem can occur in Linux if avahi (the daemon which does the advertising) is configured to use both IPv4 and IPv6. [3] The post in question suggests it's a bug.

What has worked for me is to edit /etc/avahi/avahi-daemon.conf, changing the line "use-ipv6=yes" to "use-ipv6=no". After rebooting, I reliably get the expected hostnames reported in, say, Angry IP Scanner.

I'm hesitant to suggest the above is a universal solution but it works for me.

Regards,
Kent

PS - I'm doped up with cold meds; any mistakes here are their fault!

Footnotes:

[1] yes, I know why this occurs. Someday I'll  post an issue to the repo.

[2] it's especially annoying because I haven't nailed down the circumstances under which this happens and when it doesn't

[3] I should note that my LAN all the way through to the Internet is dual IPv4/IPv6. As an aside, this also seems to introduce an issue that crops up when moOde is configured to use a static IP, but that is properly the subject of another thread when i can get around to it.

[DRONE7]

Code:

:~$ sudo arp-scan --localnet  --ouifile=/usr/share/arp-scan/ieee-oui.txt --macfile=/etc/arp-scan/mac-vendor.txt
[sudo] password for bob:          


192.168.xxx.26    Raspberry Pi Trading Ltd
192.168.xxx.26    Raspberry Pi Trading Ltd (DUP: 2)

Interesting, often whilst booting MoOde and monitoring via arp-scan (to check when it is up and can be found from browser) there will appear 2 IP results both the same address but the second noted as "(dup-2)"

This resolves to one ip once fully booted.

[Tim Curtis]

My Mac for example sometimes has moode and moode-2 in its Network locations. I'll try the avahi change and see what happens.

[TheOldPresbyope]

Code:

:~$ sudo arp-scan --localnet  --ouifile=/usr/share/arp-scan/ieee-oui.txt --macfile=/etc/arp-scan/mac-vendor.txt
[sudo] password for bob:          


192.168.xxx.26    Raspberry Pi Trading Ltd
192.168.xxx.26    Raspberry Pi Trading Ltd (DUP: 2)

Interesting, often whilst booting MoOde and monitoring via arp-scan (to check when it is up and can be found from browser) there will appear 2 IP results both the same address but the second noted as "(dup-2)"

This resolves to one ip once fully booted.

Suppose I have a moOde player with hostname moode and IP address 10.0.0.32. If I boot it several times, I can still reach it at 10.0.0.32* but whether or not I can reach it at moode.local depends on the avahi-daemon issue.

I think this early duplication you observe is what leads to the (buggy) avahi-daemon behavior. I've just seen it suggested on the InterWeb™ that a workaround is to stick a line in rc.local to restart avahi-daemon after the system has finished booting. 

(@Tim Curtis ) I confess I didn't try modifying rc.local but seems like it may work just as well as my first suggestion.

Regards,
Kent

* assuming the lease hasn't timed out and DHCP perversely assigned a different IP address to the MAC.