|
|
A lot of modern devices can use a process called APIPA to get an IP address in the absence of a DHCP Server. Under APIPA clients literally "make up" and IP address and use it. Such addresses always begin 169.254.... That will "get them working" but notably, the devices (very probably) won't get an Internet connection and half your network might not be talking to the other half.
So, check out the IP addresses you devices have (on the devices themselves, not the router) - if they are getting APIPA addresses, it's a good sign DHCP is not working properly.
You say you have reset you router to factory defaults. If so, go into it's settings and verify that the DHCP Server (note, "DHCP Server" not "DHCP Client" - the router will have both) is enabled and make a note of the IP address range it is serving out. Most routers also have a page where you can inspect the DHCP Leases it has granted - have a look through that and see what it has given out.
Even then, if you have reset your router, then it can screw up the IP addressing as the router will have lost it's knowledge of any leases it previously granted and may thence issue duplicates which can cause problems. Power cycling all your client device might help expedite solving that issue, but usually if you just leave it all alone for 24 hours, it will sort itself out automatically.
Thence it's a case of monitoring and seeing whats happening. Using typical settings, DHCP leases are granted for 24 hour and a client will start trying to "renew" their leases after 12 hours. The idea is, that having been granted a lease a device is entitled to use it for the lease time (24 hours) and be sure that their lease (IP address) won't be granted to anything else, but after half the lease time the client start asking for a "refresh" of the lease (ie get an extension for another 24 hours) after half the lease time. The process is such so that the network doesn't fall to bits because the DHCP server goes down for a short time, or the network is so busy the renewal fails (the latter being highly unlikely in a lightly loaded SOHO network.)
Not pertinent to your problem, but subsequently, you might care to "fix" the IP addresses of infrastructure components such as NAS's servers, printers and so forth so that they always get the same IP address (technically, they can vary each time they renew though it rarely happens.) Most DHCP Servers will have some options in the DHCP Leases list to "always assign this IP address to this device" (nomenclature varies between manufacturers.)
After that, we'll have to get into cases, but in the first instance let's give your network the opportunity to stabalise after resetting the firmware in your router - ie give it 24 hours then see whats happening and refrain from any further "reset to factory defaults" of your router.
If you are unfamiliar with how IP addressing and particularly DHCP work, it can have you tearing your hair out as seemingly "magic," unpredictable and random things apparently happen. Fortunately, there are a few of us who inhabit (or is it "infest") this forum who know what's up and can help you through it. |
|
2-12-2019 04:51:11
Author