Wow that's hot! Well that's a good enough reason for a spin down.
So - I did a little experiment. I have no idea if this would achieve your aim of disc spin down when alarm recording to the NAS - but it looks like you can set up a symbolic link from the file logCurFile.bin in the NAS folder the camera creates to the NAS /tmp mount point which is in RAM. But depending on your NAS model, and firmware, this can be a bit light on free space. Mine isn't too bad at 64MB, some have 32MB.
And the camera seemed quite happy to use it, recording on alarm events and still being able to retrieve the log file entries on the camera web admin.
And here is a shortened transcript of command-line activities on the QNAP NAS, which hopefully you can make some sense of.
I created a folder called /tmp/cam to hold the logCurFile.bin which I copied in before deleting it from its original location and creating the symbolic link.
Then I activated an event-based recording schedule and wandered around outside for a bit.
It seemed to work OK. But be aware - the file contents won't survive a reboot, and I don't know if the camera will simply recreate the file, or treat the NAS share as 'uninitialised' after reboot.
[/share/CACHEDEV2_DATA/cctv1/datadir0] # rm logCurFile.bin
<ir0] # ln -s /tmp/cam/logCurFile.bin logCurFile.bin
[/share/CACHEDEV2_DATA/cctv1/datadir0] # ll
drwxrwxrwx 2 IPcam everyone 12.0k Feb 11 11:44 ./
drwxrwxrwx 5 admin administ 4.0k Feb 11 11:38 ../
-rw-rw-rw- 1 IPcam everyone 512 Feb 11 11:39 HIKWS
-rw-rw-rw- 1 IPcam everyone 7.8k Feb 11 11:37 backupinfo00.bin
-rw-rw-rw- 1 IPcam everyone 7.8k Feb 11 11:37 backupinfo01.bin
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00000.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00000.pic
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00001.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00001.pic
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00002.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00002.pic
[snip]
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00245.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00246.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00247.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00248.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00249.mp4
-rw-rw-rw- 1 IPcam everyone 4.9M Feb 11 11:37 index00.bin
-rw-rw-rw- 1 IPcam everyone 4.1M Feb 11 11:37 index00p.bin
-rw-rw-rw- 1 IPcam everyone 4.9M Feb 11 11:37 index01.bin
-rw-rw-rw- 1 IPcam everyone 4.1M Feb 11 11:37 index01p.bin
lrwxrwxrwx 1 admin administ 23 Feb 11 11:44 logCurFile.bin -> /tmp/cam/logCurFile.bin
-rw-rw-rw- 1 IPcam everyone 30.5M Feb 11 11:38 logMainFile.bin
# Activate a recording schedule.
[/share/CACHEDEV2_DATA/cctv1/datadir0] # ll
drwxrwxrwx 2 IPcam everyone 12.0k Feb 11 11:44 ./
drwxrwxrwx 5 admin administ 4.0k Feb 11 11:38 ../
-rw-rw-rw- 1 IPcam everyone 512 Feb 11 11:39 HIKWS
-rw-rw-rw- 1 IPcam everyone 7.8k Feb 11 11:37 backupinfo00.bin
-rw-rw-rw- 1 IPcam everyone 7.8k Feb 11 11:37 backupinfo01.bin
-rw-rw-rw- 1 IPcam everyone 256.0M Feb 11 11:51 hiv00000.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00000.pic
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00001.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00001.pic
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00002.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00002.pic
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00003.mp4
[snip]
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00243.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00244.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00245.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00246.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00247.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00248.mp4
-rw-rw-rw- 1 IPcam everyone 0 Feb 11 11:37 hiv00249.mp4
-rw-rw-rw- 1 IPcam everyone 4.9M Feb 11 11:51 index00.bin
-rw-rw-rw- 1 IPcam everyone 4.1M Feb 11 11:37 index00p.bin
-rw-rw-rw- 1 IPcam everyone 4.9M Feb 11 11:51 index01.bin
-rw-rw-rw- 1 IPcam everyone 4.1M Feb 11 11:37 index01p.bin
lrwxrwxrwx 1 admin administ 23 Feb 11 11:44 logCurFile.bin -> /tmp/cam/logCurFile.bin
-rw-rw-rw- 1 IPcam everyone 30.5M Feb 11 11:38 logMainFile.bin
[/share/CACHEDEV2_DATA/cctv1/datadir0] # ll /tmp/cam
drwxr-xr-x 2 admin administ 60 Feb 11 11:42 ./
drwxrwxrwx 14 admin administ 2.3k Feb 11 11:54 ../
-rw-r--r-- 1 admin administ 15.3M Feb 11 11:42 logCurFile.bin
[/share/CACHEDEV2_DATA/cctv1/datadir0] #
[/share/CACHEDEV2_DATA/cctv1/datadir0] #
[/share/CACHEDEV2_DATA/cctv1/datadir0] # df
Filesystem Size Used Available Use% Mounted on
devtmpfs 496.8M 4.0k 496.8M 0% /dev
tmpfs 64.0M 17.9M 46.1M 28% /tmp
tmpfs 502.0M 28.0k 501.9M 0% /dev/shm
/dev/md9 515.5M 136.9M 378.6M 27% /mnt/HDA_ROOT
/dev/mapper/cachedev1 1.9T 1.7T 277.5G 86% /share/CACHEDEV1_DATA
/dev/mapper/cachedev2 199.1G 414.9M 198.2G 0% /share/CACHEDEV2_DATA
/dev/md13 371.0M 207.7M 163.3M 56% /mnt/ext
tmpfs 32.0M 0 32.0M 0% /.eaccelerator.tmp
[/share/CACHEDEV2_DATA/cctv1/datadir0] #