Router Keeps Restarting? Causes and Fixes
A router that reboots by itself usually has a power, heat or firmware problem. Here is how to find the cause and fix it.
A router that restarts on its own drops every device for a minute or two each time. The cause is usually one of a few things: a weak power adapter, overheating, buggy firmware, a scheduled reboot, or your ISP pushing updates.
A router that restarts on its own usually has a weak power adapter, overheating, buggy firmware, a scheduled reboot, or your ISP pushing updates. Check the simple causes first, and if none fit, the router may be failing.
Check the simple causes first. If none fit, the router may be failing.
Causes and fixes
- Scheduled reboot: check System or Administration for a reboot schedule and turn it off if you did not set it.
- Power adapter: a loose plug or weak adapter causes random reboots. Plug directly into the wall and try a matching adapter.
- Power strip or UPS problems: test another outlet.
- Overheating: give it space, keep it off carpets and out of cabinets, and clean dust from vents.
- Firmware bugs: update the firmware, or roll back if problems began after an update.
- ISP updates: provider gateways may reboot overnight to update. Ask your ISP if it happens at the same time each day.
- Too many devices or connections: older routers can crash under heavy load, especially with torrents.
- Faulty settings: back up, then factory reset and set up again.
- Failing hardware: if it still reboots after a reset, replace the router.
When a router reboots on its own, the power adapter is the first thing I check.
How to tell what is happening
- Check the router system log for reboot reasons.
- Note the time of each restart. Regular times point to schedules or ISP updates.
- Watch the power light. If all lights go off, it is power. If only internet drops, it may be the line.
Regular restart times are the giveaway for me: schedules and ISP updates run on a clock.
Heat is the quiet killer
Routers run all day, and many sit in cupboards, behind TVs or under piles of paperwork. When they overheat, they protect themselves by rebooting. Signs include the router feeling hot to the touch and restarts happening more on warm days or in the evening.
- Give the router space on all sides.
- Stand it upright if it’s designed that way.
- Keep it out of direct sunlight.
- Clean dust from vents with a dry brush.
Heat is the cause I suspect first when restarts cluster on warm evenings.
Power problems
A worn power adapter is a classic cause of random restarts. The adapter may still power the router but can’t supply enough current when the router gets busy.
- Make sure you’re using the original adapter, or one with the exact same voltage and amperage.
- Plug directly into the wall, not a crowded power strip.
- Try another socket in a different room.
- If you have frequent power dips, a small UPS keeps the router stable.
I always check the original adapter before I blame the router itself.
Check the router’s logs
- Log in to the router and look for System Log or Event Log.
- Look for entries just before each restart.
- Messages about watchdog, kernel panic or memory point to firmware or hardware issues.
- Messages about WAN or DSL dropping point to your line.
If restarts started right after a firmware update, check whether a newer version has been released, or roll back if your router allows it.
My first stop in the log is the entry just before each restart.
Firmware bugs and scheduled reboots
Not every restart is a fault. Many routers have an auto-reboot or maintenance schedule, often set for the early hours, and ISP gateways may restart after remote updates. Check System or Maintenance settings for a schedule before worrying.
If restarts started right after a firmware update, the update may have a bug. Check the maker’s site for a newer version or a known issue. Some routers let you roll back to the previous firmware from the same page.
A rollback is the step I take when the trouble starts right after an update.
Rule out your ISP line
- Check whether the router actually reboots (all lights go off) or just loses internet (only the internet light changes).
- If it only loses internet, the line or modem is the likely cause.
- Look at the modem or ONT lights when it happens.
- Note the times and contact your ISP with the pattern.
A router that loses its connection looks a lot like one that restarts, but the fix is completely different.
| Cause | Fix |
|---|---|
| Scheduled reboot | Check System or Administration for a reboot schedule and turn it off if you did not set it. |
| Power adapter | Plug directly into the wall and try a matching adapter. |
| Power strip or UPS problems | Test another outlet. |
| Overheating | Give it space, keep it off carpets and out of cabinets, and clean dust from vents. |
| Firmware bugs | Update the firmware, or roll back if problems began after an update. |
| ISP updates | Ask your ISP if it happens at the same time each day. |
| Faulty settings | Back up, then factory reset and set up again. |
| Failing hardware | If it still reboots after a reset, replace the router. |
Lights going dark is the test I trust to separate a reboot from a line fault.
