Ping feature should support pinging hosts by name

[jhol]

The ping feature currently only supports pinging hosts by their IP addresses. On my network, my non-server machines use non-static DHCP, but with mDNS. Therefore I need to be able to ping host by host name e.g. mypc.local.

[seriousm4x]

This is already possible. The input fields are labeled as IP but you can also enter a fqdn. I just checked on my local instance.

[jhol]

Weird - I tried doing that earlier, but it gave me errors.

[ERROR] 2023/12/31 12:38:49 ping.go:16: lookup nethermost.local: device or resource busy

Anyway, if this is supposed to work, I think the label could be clearer.

[ProsperAdmin]

I'm also unable to ping by Hostname/FQDN/mDNS. Log says this every 3s for every host with an address instead of an IP:

[ERROR] 2024/02/17 11:42:35 ping.go:21: lookup DESKTOP.local on 127.0.0.53:53: server misbehaving

And if I manually try to wake up that host (which is already turned on, btw):

[INFO] 2024/02/17 11:42:36 wake.go:16: Wake triggered for My PC
[ERROR] 2024/02/17 11:42:36 handlers.go:31: ip not a valid ipv4 address

Same thing for a host that is actually turned off:

[ERROR] 2024/02/17 11:49:02 ping.go:21: lookup DESKTOP-JANE.local on 127.0.0.53:53: server misbehaving
[INFO] 2024/02/17 11:49:03 wake.go:16: Wake triggered for Jane PC
[ERROR] 2024/02/17 11:49:03 handlers.go:31: ip not a valid ipv4 address
[ERROR] 2024/02/17 11:49:05 ping.go:21: lookup DESKTOP-JANE.local on 127.0.0.53:53: server misbehaving

If I use an actual IP instead of a name, everything works fine

Using UpSnap 4.2.5 in a Docker container (via Portainer "stack"), with the following composer file:

version: "3"
services:
  upsnap:
    container_name: upsnap
    image: ghcr.io/seriousm4x/upsnap:latest
    network_mode: host
    restart: unless-stopped
    volumes:
      - data:/app/pb_data
    environment:
      - TZ=America/Sao_Paulo
volumes:
  data:

Host is an Ubuntu 22.04 server with systemd-resolved active at default settings, and I can ping both machines by name, i.e. ping DESKTOP.local works fine from host.

Any ideas?

[seriousm4x]

I did a little research what the issue here could be. I think it's an issue with docker using the host network: moby/moby#38531

Maybe explicitly telling docker what dns to use will fix it. For you docker-composer.yml, try:

version: "3"
services:
  upsnap:
    container_name: upsnap
    image: ghcr.io/seriousm4x/upsnap:4
    network_mode: host
    restart: unless-stopped
    volumes:
      - ./data:/app/pb_data
    dns:
      - 192.168.0.1

Or docker run --dns 192.168.0.1 ....

[ProsperAdmin]

Not sure why changing the DNS entry will help solving multicast (mDNS) resolution. My DNS "server" is my router, but it acts just as a relay for my ISP's DNS Server, and it does not resolve host names in the LAN. But let's try anyway:

With the dns entry pointing to my router IP, error changes to this:

[ERROR] 2024/02/17 13:05:22 ping.go:21: lookup DESKTOP.local on 10.1.1.1:53: no such host

And of course, 10.1.1.1 exists, I can ping it just fine. But it was expected it could not resolve .local addresses.