Anyone else seen this.

Don't think my 2865 has, have you been keeping up with recent firmware fixes?

I sat my phone on my thunderbolt dock while it was charging, and it complained the battery was getting too hot and stopped the charge.

Just checked, uptime is nearly 2 months, which roughly corresponds to the most recent draytek downloads on my laptop.

I have a Draytek 2927 series - it is not new to me, but was previously used in a commercial environment with no issues AFAIK.

I have noticed a situation with mine where the connection both wired and wireless) appears to drop momentarily, on occasion (couple of times a week?)

I recently looked at the log, and saw something similar to what you describe - the router was in fact rebooting, and the log shows something like:

Router Model: Vigor2927ax Version: 4.5.2 English Profile version: 4.0.0 Status: 1 (0x9de71d0f) Router IP: 192.168.0.1 Netmask: 255.255.255.0 Firmware Build Date/Time: Feb 12 2026 17:45:01 Router Name: DrayTek Revision: 6562_fd593bfca2 drayos2015 Router serial no: None

---------firmware exception debug info on cpu0-----------------------------

# etc.

There are a few Draytek support pages around this, and typically they want to blame the PSU. My PSU is not the original Draytek, but can supply substantially more current - 4.5A IIRC, so I doubt that is the issue.

My router is not in one of the hotter places in the house. I have just felt it now, it is pretty warm though. I may try to lift it up off the shelf it sits one, for more airflow, to see if that makes a difference

(I should say that I think my issue has pre-dated the recent heatwaves)

J^n

You can get bit flips from cosmic rays. That's a reason servers have ECC memory:

It could also be a RAM chip on the way out.

Theo

In message <1128k1p$3fgrb$ snipped-for-privacy@dont-email.me, The Natural Philosopher snipped-for-privacy@invalid.invalid writes

I've got a Vigor 2865 which rebooted a week or so back, there wasn't a power cut, so I'm assuming that the router did it itself. I thought I had logging turned on, but apparently not.

The room it is in doesn't get that warm (upper 20s at the time).

Adrian

PS: my router rebooting seems to happen more often when I power up a laptop, ie. new WiFi connection(s) have to be made.

This lends some credence to the idea of it being a PSU issue, at least in my case. But as I say, I have an overrated PSU connected. Perhaps I will try the original Draytek one, as an experiment...

Dunno about any of that but my VDSL modem crashes in warm weather. Taking the board out of the plastic case and blowing a USB desk fan across it seems to sort it out.

This year it pissed me off enough to order FTTH.

Not a router but my Freesat box turned the HDD off a few times in the heatwave due to over heating.

Not noticed any particular pattern of reboots with the current one (2927), the previous 2865 might have restarted more frequently - but even then only 2 or 3 times a year.

(I think if they detect a sequence of boot time fails, they will revert to the previous version of the firmware just in case it was a firmware update that caused the problem)

The FTTP sometimes drops out for 10 mins at midnight once every few weeks, but I expect that is a ISP issue or something on the PON.

I have a temperature sensor plugged into one of the USB ports on the router, and the graph is showing a daily cycle between 40.2 and 40.6 deg C at the moment. (it is in a 12U 19" comms cab - but the door is open)

No computer misbehavior here.

If the behavior is consistent across reboot that suggests a problem somewhere more persistent than RAM. Flash corruption would be my first guess.

Page caching can make RAM corruption very persistent (albeit not across a reboot). A while back chiark’s /bin/cat developed a single-bit error in the cached copy of the code section, which was used (without reloading) every time it is executed.

Yes

Normally that router is flawless. stays up till the next power cut of system upgrade.

Ive reflashed the same firmware. Its the latest. We will see.

Yes. that is significant. Its the next bit of the log before the registers dump that is significant

Mine said (in shorthand) 'The CPU tried to execute an instruction that does not exist'

My tentative conclusion was that the firmware in flash was corrupted.

Mine is original and has given no trouble before

Although I am on FTTP mine is still plugged into the phone line - there have been storms...

Well I reflashed my firmware. We will see. The router was not doing anything special at the time.

Well its rebooted and then done it again a few hours later. That doesn't rule out dodgy RAM but it inclines towards Flash,,,

Very interesting possibility..

You can use the systems internal crash log..

full instructions here

Could be Tham Thar Kosmik Rays...

Aren't we (solar system) moving into an area of higher galactic radiation?

It's comforting to know that other people have had this happen.

Mine used to crash and stay crashed after local thinderstoms

I've had one genuine outage on mine. In a couple of years. Sometimes it flaps for a second or two, but compared to ADSL its magic

Yes, my log has:

---------firmware exception debug info on cpu0----------------------------- EPC=60034b60, Cause=00800014, Status=1100fc03, BadAddr=00000000, RetAddr=60034a58 exception id=5(ADES: Address Error Store) exception occured in TASK Level task_id=161, SP=0x629390b8(3188 bytes free, 5664 used bytes) system tick =26381273 CURRENT_VERSION : 4.5.2_RC5 get from address : 60017000 Dump CPU0 registers: ...

but if you look eg. here:

Hi John how does that temperature sensor bit work please?

There is a 'USB Application | Temperature Sensor' menu entry on my Draytek, but I don't know what it needs to work...

Thanks J^n

Yes. This is the debug output This error seems not uncommon found half a dozen examples of it reported

From the console:

Type ? for command help > sys ver dbg

Router Model: Vigor2762Vac Version: 3.9.9.5_BT English Profile version: 3.0.0 Status: 1 (0xb1d7bc56) Router IP: 192.168.0.254 Netmask: 255.255.255.0 Firmware Build Date/Time: Nov 12 2025 11:09:16 Router Name: DrayTek Revision: 24438_1228_23c13bbb0d V385 Current ADSL Firmware Version: 07-07-03-0F-00-01 Annex A ADSL Firmware Version: 07-07-03-0F-00-01 Annex A VDSL2 Firmware Version: 07-07-09-05-01-07 Router serial no: 185003615566

---------firmware exception debug info----------------------------- EPC=80b3397c, Cause=80800028, Status=1100fc03, BadAddr=0000000c, RetAddr=80b3397c exception id=10(RI: Reserved Instruction) exception occured in IdleTask Timeout task_id=110, SP=0x81de1980(3178 bytes free, 5704 used bytes) system tick =3060436 CURRENT_VERSION : 3.9.9.5_B get from address : 80004000 Dump CPU registers:

----------------------------------------- $ 0: 00000000 fffffffe 846f7c00 00000d85 $ 4: 00000d85 00000001 00000700 00000004 $ 8: 81de1340 00000001 00000002 afbf0000 $12: 81de1958 80ff2000 00000000 653a3230 $16: 0000000c 000003a6 83687680 00001438 $20: 83960200 81de1e58 824f9573 00000000 $24: 00000010 00000030 000003a6 00000000 $28: 815e2e40 81de1980 00000230 80b3397c List a possible caller functions:

---------------------------------- func( 0)=80b318b0 func( 1)=8097d660 func( 2)=8097fde8 List backtrace functions:

---------------------------------- func( 0)=80b3397c func( 1)=80b318b0 func( 2)=8097d660 func( 3)=8097fde8 >

On 7/3/26 22:09, Richard Kettlewell wrote: ed image in flash to reduce flash cost

vmtouch?