What happens when router has been set to incorrect time?

Question

I have a D-Link router for my home Wi-Fi network. Everyday at least once the internet suddenly goes down. I am simply not able to connect to the Wi-Fi network.

If I just restart the router, it starts working. To debug the issue I logged into the admin panel and noticed the time was set to something in 2002. I have set it to the correct time. Will wait to see if that fixes the problem.

In the meanwhile I want to know what can go bad when the router has been set to show an incorrect time? What are the kinds of problems expected?

My Wi-Fi was working just fine most of the time, but sometimes it lost the connection. Could this be linked to the incorrect time setting?

Solution 1

Generally router functions are not affected by having the wrong time as long as the time is consistent. Problems will occur is the time is being randomly reset. So if your router boots up and thinks it's 2002, it will run quite happily, pretty much forever, as long as the time doesn't suddenly change.

Also, even if it does change via NTP, leases etc will be correctly adjusted as a time reset by NTP is a normal expected event and most times are stored as offsets/differences so won't need altering anyway (a time counting down a given number of seconds will continue to count down).

• Leases are allocated based on a time difference, so as long as the time is consistent this won't be a problem
• The WAN assignment will similarly be a time difference, so shouldn't suddenly expire
• Running NTP on the router will, obviously, not work correctly is the router's time is wrong, but, if this was the case you'd have noticed it sooner
• Logs will we incorrectly timestamped, but presumably you haven't been checking these (if they exist)
• If your router has NAS features, the file timestamps may or may not be affected, depending on the exact implmentation, since often the connecting client sets the date/time on files directly

Overall, having the wrong time on the router shouldn't affect your wifi connections, but it's probably a good idea to set it correctly, ideally via an NTP setting.

A more significant problem may be if the time on your router randomly resets as this may indicate that the router has a fault.

Solution 2

A faulty firmware update may cause a router to behave this way. You may wish to manually upgrade the firmware in you router configuration, if the following potential problems cannot be resolved:

• You may see lease expiration issues. A simple workaround for that is to reserve the appropriate LAN IP addresses in your router config for each LAN device.

• If the router's WAN IP address is dynamically assigned by your internet provider, a router's DHCP address assignment may be affected. Routers having connectivity issues may be experiencing this. You should try using another NTP server in your router's configuration.

• If you have any services like NTP running on the router, the incorrect time and date is assumed by LAN clients.

• Your logs will be incorrectly time stamped.

• If your router has any NAS features (like a USB port where you can plug in a USB hard drive to be shared with the network via SMB), then your file creation/modification time stamps will be wrong.

• Scheduled crontab events on the router may never trigger.

Comments

[Daniel R Hicks]

When our router hangs it's usually because the internet connection went down and didn't come back up cleanly. Never even thought of checking the router time, but I don't see how it could have an effect.

[Daniel R Hicks]

Yeah, I've seen similar on my router from time to time. But I suspect that it has to do with the DNS setting getting mucked up, and one system may pick up the new (bad) setting while another sticks with the old (good) one, just based on when they renew their leases.

[Colonel Panic]

Rohit, your connection issues might have nothing to do with the router (X Y problem). To test that, connect a computer directly by ethernet to your modem.

[Francisco Tapia]

it could be the DHCP lease from your network provider, they usually haves dinamic ip addressing and when renew they got another one diferent than before, that is because they do not want you to up services because you are a home user, and the network took a little time to converge.

[100rabh]

ntp1.dlink.com has been down since quite some time, fyi..

[100rabh]

in my case when I last checked name resolution itself was failing.

[zero2cx]

@StarNamer This quote describes a DHCP server compensating workaround: "If there is drift between the two clocks, the server may consider the lease expired before the client does. To compensate, the server may return a shorter lease duration to the client than the server commits to its local database of client information." Does the server workaround entirely resolve all lease expiration hiccups? My judgement says that one reset after another can defeat the described workaround, but I would welcome clarification. Thanks.

[Sam]

your answer is not giving more information than others