# HDDs won't spin down since running "udevadm trigger net"

## Jarjar

After trying (well, succeeding) to change my MAC address in /etc/udev/rules.d/70-persistent-net.rules and running "udevadm trigger net", my three idle disks refuse to spin down - they power up the same second they are shut down. They are not mounted and appear to not be accessed, according to iostat. (Hard to tell in that timeframe, though... but they aren't accesed when spun up.) They are also part of a 3-disk md RAID5 array, that is stopped.

The system has been up for 214 days and the problem started within 5 minutes of my last modification of 70-persistent-net.rules, so this is hardly a coincidence.

hdparm/udevadm monitor output:

```

(13:36) exscape ~ # hdparm -y /dev/sdb

/dev/sdb:

 issuing standby command

(13:36) exscape ~ # hdparm -C /dev/sdb

/dev/sdb:

 drive state is:  active/idle

-- In another window, started before any hdparm commands were sent --

(13:36) exscape ~ # udevadm monitor

monitor will print the received events for:

UDEV - the event which udev sends out after rule processing

KERNEL - the kernel uevent

KERNEL[1262522217.633318] change   /block/sdb (block) <-- when shutting it down

UDEV  [1262522219.023900] change   /block/sdb (block)  <-- when shutting it down - or is this the startup? 1.4 seconds after the kernel event.

KERNEL[1262522226.228927] change   /block/sdb (block) <-- when using hdparm -C to check status 7 seconds later

UDEV  [1262522226.335246] change   /block/sdb (block)  <-- when using hdparm -C to check status 7 seconds later

```

What the heck? Why is it not staying powered-down?

I have little experience with udev, but I touched *nothing* except now-reverted changes to the MAC matching/NIC naming rules, and running "udevadm trigger net".

If I run "udevadm control --stop-exec-queue" the disks stay off, until I run start-exec-queue. I take it I can't just disable this forever, so... Ideas?

Thanks in advance.

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## Jarjar

Any ideas?

sdc is working now (since about an hour after posting), starting and stopping as it should, but sdb and sdd have been running 24/7 (well, since they have no standby timer,  that's no surprise) and won't shut down for more than a second when told to.

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