Can you tell me how to reserve IP addresses for permanent devices please?

Hi @UKMedia.

Thank you for this very educational and informative post.

This is a great help for other members of the community to better understand how a router works, IP addresses, and possibly avoid IP address mismatch and duplicate IP-addresses, double NAT (network address topology), and have better local communication within their WiFi/Network system. 

This is a good read and I hope this helps a lot more members in the community especially topics about rooms missing from the Sonos app.

Thanks for sharing,

Sometimes a Sonos system just starts to behave in a random inconsistent manner.  There can be many reasons for this but a common cause is duplicate IP addresses within your home network.  Other network devices that are not dependant upon inter-communication can be unaffected but the really frustrating thing is that there is no easy way to confirm that your network has this issue.

I have written this post to try and explain what duplicate IP address actually means, how it is caused and how to stop it happening again.

As a general comment, when trying to resolve Sonos issues and you feel the need to reboot the Router, it is ALWAYS advisable to reboot ALL connected devices within the home. (I know this is a pain but please read on)

For those of you reading this that aren't totally clear on how this works, I’ll try and explain below:

• Each time a new device connects to your Wi-Fi or is plugged into an Ethernet cable, a device (normally your Router) allocates it a unique network (IP) address;
• Normally this address is in the format of 192.168.0.1 (This specific address is normally reserved for the Router) and then the next device to connect is allocated the next number - 192.168.0.2 and so on;
• The issue occurs when the Router is rebooted, as the Router then loses any knowledge of the addresses previously allocated and so will start from 192.168.0.2 again;
• Any devices within your network that have not been rebooted at the same time will continue to use the IP address that they were allocated before the Router was rebooted;
• So, an example scenario of a household with 20 connected devices, including 5 Sonos devices would mean that the next device to connect would be allocated 192.168.0.22 and all is stable. However, as soon as the Router is rebooted and the previously allocated addresses are lost, the Router will then allocate 192.168.0.2 to the next device – meaning that there are now two devices with the same IP address within the Network.  If the Sonos devices are then rebooted, these will also be allocated addresses that had previously been allocated before the Router was rebooted and so the problem gets worse;
• For standalone devices, this can often go unnoticed by the user but for devices that need to communicate with each other (Sonos, Alexa and GA devices) this will cause a lot of seemingly unrelated performance and functional issues;

The ONLY way to resolve this issue is to reboot your network in this order:

• Router
• Any wired Network devices or switches;
• Any other wired devices;
• All other Wi-Fi devices (Turning Wi-Fi off and on again on each device would also work)

The way that you can reduce the effect of this problem is to reserve an IP address within your Router Set-Up for all permanent devices. This ensures that a device is never just allocated the next IP address that the Router ‘thinks’ is free.  I personally use the range 192.168.0.175 – 192.168.0.244 for my devices that are connected to my network on a regular basis.  This removes the requirement to reboot these devices whenever the Router is rebooted, as they will always be allocated the exact same address and the Router will NEVER allocate this address to another device.