Ping not finding local devices by name

[MymsMan]

For many years I have had network-shares-automount configured to access my NAS using the host name LS220D3B1 but recently I noticed it wasnt connected and the log shows ping: bad address 'LS220D3B1'
The humax can ping itself by name but none of my other local device by name, it can ping by numerical address and ping external sites by name (eg google.com)

I have changed ISP from Plusnet to Three and the Humax now has a wired connection to the new eero router so that may be the cause but all of my windows computers can still ping all my local devices by name.

ping  LS220D3B1

Pinging LS220D3B1 [192.168.4.23] with 32 bytes of data:
Reply from 192.168.4.23: bytes=32 time=2ms TTL=64
Reply from 192.168.4.23: bytes=32 time=4ms TTL=64
Reply from 192.168.4.23: bytes=32 time=3ms TTL=64
Reply from 192.168.4.23: bytes=32 time=4ms TTL=64

Ping statistics for 192.168.4.23:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 2ms, Maximum = 4ms, Average = 3ms

Obviously I can switch to using numeric addresses but they are less convenient

Any ideas why the humax can no longer ping local names? and how to fix it?
I don't have anything defined in iptables

 

[Black Hole]

This may be a simplistic answer, but as I understand it, in order to address a device by name, there has to be something on your network able to convert the name to an IP address. I think there are a variety of protocols for this, but as you have changed your router, it seems logical to consider mechanisms which involve the router,

Could it be that your old router had the DNS in its DHCP table, which has not been rebuilt in the new router? You might have assigned device names by manually entering them against their MAC in the router's address allocation table, or I believe devices can announce their names when registering with the router by DHCP.

The information could also be local to your HDR-FOX, in the hosts file, but as you have not changed the 'fox...

 

[bottletop]

..Obviously I can switch to using numeric addresses but they are less convenient

Does this mean that you can ping each device to all others using IP address?
It could be you had something like Avahi/Zeroconf configured on the old router that you don't have on the new one.
Alternatively I installed Zeroconf on my HDR and can ping it (from another device) using ping <hostname>.local

 

[MymsMan]

A bit more digging shows that the problem extends to other devices including my Android mobile phone which used to be able to connect to the humax and other devices by name can't

Alternatively I installed Zeroconf on my HDR and can ping it (from another device) using ping <hostname>.local

I do have zeroconf installed on the humax - but still cant ping it from phone using either humax or humax.local

The basic problem appears to be that the eero does not have an inbuilt DNS server that local devices can post their names to, instead everything goes to the internet DNS servers.
Windows computers can still find local devices using NetBIOS which linux based machine don't use.
I can configure the DNS servers used by the eero but that doesn't really help me if I don't have a local DNS server

 

[Black Hole]

It might be a pain, but you could maintain a hosts file and copy it to all your devices as a form of manual DNS.

Alternatively, perhaps an always-on device (HDR-FOX?) could run a local DNS server.

 

[MymsMan]

I have

It might be a pain, but you could maintain a hosts file and copy it to all your devices as a form of manual DNS.

Alternatively, perhaps an always-on device (HDR-FOX?) could run a local DNS server.

I have tried adding entries to mod/etc/hosts (and rebooting) without success

127.0.0.1    localhost
192.168.4.23 ls220d3b1
192.168.4.25  mymsmanacer

EDIT I need /root/etc/hosts instead !
But that doesn't survive reboot so an init.d routine needed to copy it across

Strangely /root/etc/hosts does contain an entry pointing to a Canon printer, something I have never tried to access from the humax - I wonder how that got added but not more useful devices!

127.0.0.1    localhost
192.168.4.26    humax
192.168.4.26    humax.local
192.168.4.32    030F69000000.local

There doesn't appear to a dns server in the package list, there is an inadyn dns client listed but doesn't appear to be what is required
The Windows DNS server I have found, MaraDNS, looks too complex for me - one of those that assumes you already know everything about setting up a DNS server

 

[Black Hole]

There doesn't appear to a dns server in the package list

I didn't intend to imply there is. My implication was that perhaps one could be compiled.