Is there a way to assign specific DNS servers to individual clients? I previously used an ASUS router, which had a feature called DNS Director. It allowed me to assign a static IP and DNS server to each client individually, which was very convenient compared to having a single DNS server for all clients.
Model : GL-XE3000 (pulli X)
Admin Panel Version 4.0
Firmware Type : 0412release3
Even if I don't know why this should be something you need - but yes, it is possible using OpenWrt itself. You will need to adjust the config files using SSH then:
The reason I need this feature is that I have multiple tablets used by my kids, where I require a safe DNS server to filter out harmful content. Additionally, I have a local instance of AdGuard and Pi-hole running on my Proxmox server, which require direct access to Cloudflare and Google DNS for proper functionality. Meanwhile, all other devices in my network rely on the local AdGuard or Pi-hole for DNS resolution.
If I configure the local DNS servers as default DNS providers in the admin panel, the LXC containers on my Proxmox server lose DNS access, effectively bringing down the entire network. I'm aware of the built-in AdGuard DNS feature, but due to the large number of ad lists I use, the built-in one struggles to handle the load, often freezing or crashing.
This is why having the option to assign individual DNS servers to multiple clients would be highly beneficial for managing my network effectively.
Thanks for the fast reply let me try config files way
Maybe you can just set up an external DNS instead of the routers DNS for your LXC?
If there is an upstream route (using DoH, DoT) it should be totally fine.
Yes, I use 1.1.1.1 and 8.8.8.8 as DNS servers for my LXCs. However, when I enable 'Override DNS Settings for All Clients' in the admin panel, those DNS settings are overwritten as it should be. This is where a client-specific DNS configuration becomes useful.
My kids are clever, and if this setting isn't enabled, they can easily change the DNS settings on their devices to bypass restrictions. That's why I need to keep the override feature turned on to ensure proper control
That's why I wrote DoH and DoT on your LXC 
Plain DNS won't work in this scenario.
I don't think Proxmox natively supports DoH or DoT directly.
You should try the Flint2, I think it's powerful enough to handle what you may throw to the adguard home built in 
yea flint 2 looks good, spec wise , but i need one with 5g , So that i can failover
Not rocket science, just plug something like this Inseego USB8 4G LTE Global USB Modem like I did and you are golden
4G in my area is terrible, and I'm barely getting 500Mbps on 5G. If things don't workout using dnsmasq, I'll switch to the Pulli AX for 5G failover and go back to using the Asus for routing.
To be honest: Even your DNS filter won't stop them, they can simply switch to a DoH / DoT resolver and your whole filter won't work anymore. DNS filtering for censoring stuff (or trying to control kids) is the most useless nonsense ever.
Apple even integrated iCloud Privacy Relay which will use its own DNS by default.
Well as of now my ipv6 is disabled and all dns querys are handled locally , ads are blocked unwanted content is filtered , the rest is a problem for another day , Only problem being this dns issue , As of now oi have added :
this to /etc/config/dhcp
config host
option name 'adguard'
option mac 'BC:24:11:56:D2:69'
option ip '192.168.1.5'
option dns '1'
list dhcp_option '6,1.1.1.1,8.8.8.8'
config host
option name 's24u'
option mac '4c:66:a6 xxx:f6'
option ip '192.168.1.21'
option dns '1'
list dhcp_option '6,8.8.8.8,1.1.1.1'
and for the time being everything seems to work
That is some misunderstanding.
All plain DNS is handled locally. But plain DNS is something that vanishes from day to day more. As soon as DNS-over-HTTPs, DNS-over-TLS or any other DNS form is used that isn't plain DNS ... it won't work anymore.
if anyone else faces the same issue just add the concerned ip to the bypass rebind protection config
which is :
dnsmasq configuration:nano /etc/config/dhcp
config dnsmasq:config dnsmasq
option rebind_protection '1' # Keep rebind protection enabled
option rebind_localhost '1' # Allow localhost responses
list rebind_domain '192.168.1.5'
dnsmasq:/etc/init.d/dnsmasq restart