Setting static IP addresses

Logically it does not make much sense for a router to reserve IP addresses outside of the DHCP range that it is managing. I would check the router's documentation to make sure that this is supported.

Hi @buzz 

After the recent refresher I just got on the subject thanks to my ISP, I agree. Static IPs should be outside of the pool, and each client device should be configured to not use DHCP and to simply take it’s static IP. With reserved IPs, the client device has DHCP turned on and requests an IP - it’s the router that remembers that this particular device should have a particular IP, which is pulled from the pool, as it is DHCP that is in use.

Strange then that my TP-Link router allowed reserved IPs from outside of the DHCP pool - perhaps they simply predicted that people might try to do so and adjusted their code to cope.

It seems that outside of network professionals, the terms “static IP” and “reserved IP” are somewhat - but incorrectly so - interchangeable. I think Static IPs are the old way of doing things that required too much work and had too many pitfalls, like needing manual configuration of each client device.

To anyone still wondering, Sonos speakers can’t be configured to take static IPs, but most routers can reserve IPs for devices and therefore Sonos devices can be given a reserved IP.

I thought otherwise; indeed the Apple utility insisted that this be done. It is like a town council handing out house numbers - the ones that are reserved should not be accessible to the pool from which unreserved ones are handed out their house number, else the reserved number may get handed out to a random house if the reserved house is offline, causing issues when latter turns up again asking for a house number. So I think at any rate.

But: When in the mood to suffer some consequence, I will expand the pool on my ISP router back to what it was, with reserved IPs then within that expanded pool and see what happens. It will be just one toggle to see the outcome.

Hi @Kumar

If you look at it from the client device’s side, it makes sense - when you use reserved IPs, the client device is still using DHCP, therefore it makes sense that the IP comes from the DHCP pool. When you set Static IPs, you turn off DHCP in the client’s settings - DHCP is not used and therefore neither should the pool be used.

On the router side, reserved IPs are reserved - they are only handed out to the associated MAC address and are not handed out to any others. Like booking a particular reserved table in a restaurant, if someone else shows up and asks for a table, they don’t get that one.

I guess you just have to meet the expectations of whoever wrote the code for each particular company/device.

Corry - that is exactly the reason why I explained in the OP the distinction between the two terms that I believe network professionals use. I have been involved in threads here before where the people contributing did not appear to understand the difference.

As stated above, my router can’t facilitate Reserved IP addresses outside the DHCP range - the User Interface provides the user with no way to configure them, because Sonos devices can do nothing other than make a request via DHCP.

Update but before that, all kits works fine through all this experimenting so there is that to also consider.

I had changed the pool to 51 - 254 and set out reserved addresses between 2-50. Devices with reserved addresses ended up with that address, or another in the pool beyond 51. 

I then reexpanded the pool back to 2 - 254, with no other changes made.

Now the same story except that all addresses are lower than 50, because there aren’t more devices.

I can also see that an address reserved for an item that has not been powered on has been given to another device that had no reservation. 

In both cases the majority of kit with reserved addresses get that address.

ISP router made by Dasan networks; google says Vietnamese.

This makes me nervous. I recommend powering down and rebooting everything if you change the DCHP pool. If the leases have all expired, been renewed, and the system is still stable, you can probably skip the mass reboot.

After toggling the DHCP pool back to its full size, I did the full reboot of everything process. As I had done when I had reduced it in size and done the IP reservations in the router. 

I could move the DHCP management to what seems to a more orthodox TP link router that, wired just downstream of the ISP router that is being eccentric, is a TP Link that is just now being used in access point mode, but I am not confident of other things I may have to change as well, to leave the ISP just as a feeder of internet to the TP Link that will then move to router mode.

So as long as things keep working, I have to leave them in the state they are!

But I think I will do another full reboot of all kit since that is just hardware powering on/off and see if things change.

Outcome - Nothing changes; most of the Sonos kit has the reserved addresses, but there are still a few that do not.

I reserve all regular network clients, SONOS or not.