NAS326 USB CAddy requirements

duggleb

I'm using a NAS326 with a USB Caddy as external storage, it appears in storage manager and maps OK

I've tried to add a new caddy & HDD but it does not appear in Storage manager. I've checked on a PC and Windows sees the drive, shows data on the disk so what am I missing when connecting to the NAS.

I've tried the rear USB and the front USB, neither shows the disk, BUT if I plug a USB memory stick into either port they appear in Storage manager as expected

duggleb

Followup

HAve got the new drive to be recognised, but then later it has dropped out again. If I power off the drive, power it back on, then unplug and reconnect the USB the drive reappears for a while, but then drops out again

Mijzelf

That could be a disk sleep problem. The NAS326 uses a daemon 'hd-idle' to spin down disks which have been idle for a (configurable) while. I think you have got an USB-Sata converter which doesn't like that, and switches the bridge off, or something like that.

A work around could be to remove the disk node from the /dev/ directory, after the filesystem is mounted. hd-idle then cannot spin-down the disk.

To test that, enable the ssh server, login over ssh, and execute

ls /dev/sd?

It should show your internal disk(s). Then plugin the usb enclosure, and repeat. Now you should see one more. When the filesystem is mounted, remove the node:

su
rm /dev/sdc

assuming /dev/sdc is your external disk. If the disk doesn't disappear now, hd-idle in combination with the usb-sata chip is the problem. Don't know if the disk keeps spinning, there could be an internal spindown mechanism.

duggleb

Thanks but when I run ls /dev/sd? I get

/dev/sda /dev/sdd /dev/sdi /dev/sdl /dev/sdo /dev/sdr /dev/sdu /dev/sdx
/dev/sdb /dev/sdg /dev/sdj /dev/sdm /dev/sdp /dev/sds /dev/sdv /dev/sdy
/dev/sdc /dev/sdh /dev/sdk /dev/sdn /dev/sdq /dev/sdt /dev/sdw /dev/sdz

I have 2 internal disks, 2 USB connected disks so where do the other 20 come from?

Mijzelf

Ah right. In that case the '326 doesn't create device nodes when needed, but has everything pre-populated.

You'll have to find another way to find out which device node to use. On method is looking at the mounts:

cat /proc/mounts

shows all mounted filesystems as '<device node> <mountpoint> <filesystem> <flags>'

On a ZyXEL NAS the internal data partitions are mounted on /i-data/* mountpoints, and the external on /e-data/*. There are more mountpoints, but you can ignore them. Probably the device node is not from a disk, but from a partition. /dev/sda is a disk, /dev/sda1 is the first partition on that disk. hd-idle uses the disk node, not the partition node. As the device node is not dynamically generated, it's better to rename it, not delete:

su
mv /dev/sdc /dev/sdc_gone

So you can easily revert when needed. (The whole /dev/ directory is created on boot, so a reboot will always revert it). As far as I know the disk node is only used for partitioning, and by hd-idle. But I might be mistaken.