Firmware version SG4K10002600t.
I can set the DNS servers for the router itself to use, on this page:
This works, because the Device Info page now lists those DNS settings:
But I can't set the DNS for LAN clients to use, on this page:
The fields are disabled. I was able to set these values before the firmware got updated but now I can't.
I still have my old HG633 router lying around so I could use that instead, but I'd prefer to use this newer, supposedly faster router. I just want this bug to be fixed in a new firmware version.
By default, they hand out the router (192.168.1.1) as the client's DNS server within the DHCP Offer. Unless you have a DNS server on your local subnet, changing this if you could, would render your DNS operation inefficient. I think this is why they have probably greyed it out.
That makes sense, but it was enabled before when I set those values. Now I can't even change it back to 192.168.1.1.
I have just had time to check mine & running firmware 2600 mine are not greyed out & I can definitely change them. I would, therefore, recommend that you try a factory default of the hub configuration.
Interesting. Have you set DNS servers for the router itself?
I will experiment. Maybe removing the DNS servers for the router (to default to TalkTalk servers) will enable the DNS server fields for the LAN.
You set the DNS servers that the router uses from the Internet Connectivity section.
Having setup a Pi-Hole at the weekend I too have discovered that the DNS settings are greyed out.
I want all the devices on my network to use the Raspberry Pi for DNS so the ad blocking works network-wide, but now the fields are disabled I can't do that.
I wasn't like that before because I have previously changed the DNS to 188.8.131.52 and 184.108.40.206 and those settings are still there, but cannot be changed.
Yes, the Sagem FAST 5364 with firmware SG4K10002600t
Have you tried a factory default of the hub's configuration? Mine, running on the same firmware is fine. I can change the DNS servers at will.
Thanks @KeithFrench that did the trick. In my brief testing all appears to be working again.