sorry for that, but I totally disagree with you @Kevin_Z . Have you figured out what the question is?

as per my understanding, it may be related to two factors:

1. assume all the devices are connected to the Deco wirelessly or wiredly, it will depends on what DNS server the Deco's DHCP server assigns to its clients.

2. assume part of the devices are connected to the Deco's network, and part of the devices are connected to the from Modem, for example via wire. In this situatio, the NAT by affect some packet passthrough.

So, we need to check:

1. what DNS IP the clients connected to the Deco network gets, is it the same as they get when they are connected to the old modem?

2. check how the network is connected. Test when the NAS and clients are connect both to the Deco's network.

To confirm. All devices are connected via the Deco. I could plug some into the ISP provide modem, but then i wouldn't be able to use the deco features (i.e parental controls on them). Most devices are wireless, some such as Hive, need a wired connection.

In essence the problem is, on a laptop/PC on the deco network I want to ssh to another device on the Deco network without having to open the deco app and find it's IP address (that in itself is a terrible user experience, because as far as I can see the only way to find an IP address is to go into the "fixed IP reservation" part of advanced settings - but thats a question for another day)

If i connect the devices directly to the ISP (BT) provided modem (either wired or wirelesly) i can do this as (i assume) the BT modem is also providing DNS resolution for internal devices (ie "ssh nas" just works).

If i move all the devices off the ISP provided modem's wifi and onto the Deco, then it stops working. This is a major show stopper for me. I need/expect to be able to find/resolve and connect to internal devices on my own network. I guess there are some answers such as to run dynDNS, etc and have each client register there, but really if BT can make this work, why can't Deco ?

@Ant_and_deco 

I am pretty sure the problem you're having now is the same as this one

(please delete www.tp-link.com to use the url) https://www.tp-link.com/serverfault.com/questions/352305/why-can-windows-machines-resolve-local-names-when-linux-cant

The reason of the problem:

You don't have local DNS server deployed in your network. Then on your local network, it's not using DNS to resolve the name.

On your local network, devices will use NetBIOS to resolve the name. But Linux system by default doesn't support NetBIOS, that's why your Windows clients can ping device name directly while your Linux clients cannot.

Solution:

as introduce on the above article, you need to install Samba on Linux system and modify the nsswitch configuration file:

To enable Windows netbios name resolution from a Linux computer, make sure that Samba is installed (although the smb service does not need to be running). The Samba suite includes winbind, which enables Windows host names to be resolved. Then edit /etc/nsswitch.conf and change this line:

hosts: files dns

to this:

hosts: files dns wins

Then test by pinging the computer name of Windows machine on the LAN:

$ ping ns

Guess:

I don't have BT modem and I am not familar with it so I am not very sure why the linux hosts can work normally before when connecting to the old BT modem. But I guess it may be because your BT modem supports built-in DNS server and can register the local devices automatically. When you ping the local devices's name, it will use the DNS to resolve the IP address. DNS is a standard protocol that both Windows and Linux support. But Deco doesn't support built-in DNS server, it can only forward the DNS requests to the external DNS server that is defined on the WAN DNS. But the external DNS don't have the records of your local network devices.

From this perspect, @Kevin_Z  is correct that Deco doesn't support. But as I know, most modern home routers doesn't support built-in DNS server and cannot register your local network devices.

Received my set of Deco X60's today, and have the same problem -- no internal DNS resolution for units on the local network, even when using the advertised DNS server on the Deco (192.168.1.1 in my case).

Highly surprised that this is not supported by the Deco; first time in more than 15 years I've had a home router with DHCP not supplying DNS.

Will send my set back for a refund...  Shame, since the rest of the package is pretty good.

Buyers beware: if you have anything more than very simple networking needs at home, the Deco will not do the job.  Look elsewhere.

@Ant_and_deco 

I agree, this is a big issue for a router.

When we buy a router, it should be an evidence that a DNS server is available. Now for me, and surely for lot of people, my network is broken. I need to set up an other DHCP server which is associated with a DNS Server

Is there a roadmap for the firmware of Deco M9 Plus? (currently version 1.4.0)

Perhaps, DNS Server is planed...

Thanks for youe help

@PPCM 

Having played with my deco for a while now, it's become clear to me it knows my device names. You can see them in its interface. They are used for parental controls, and in general for identifying devices. Why this data is not also available via local DNS seems a massive oversight.

Again, if it's not clear, deco already has the information it needs. It just needs to provide DNS resolution if no FQDN is provided

I agree with you, the DNS resolution for local devices is really needed.

Currently, I need another router for DNS service, that implies, the DCHP service of that router is used too to resolve local devices.

In my configuration, Deco mesh is only used in bridge mode, and this is a pity, because it has the potential to become a great WiFi mesh system

@Ant_and_deco Maybe not the best option but as a workaround you could create Address Reservations for the devices (so they will always get the same IP address) and then update the host file to give them user friendly names.