Why is external storage device auto mounted at /tmp/mountd/disk1_part1

Installing and Using OpenWrt
1

I bought a device pre-installed with OpenWRT 21.02 and when I plug an external memory card it gets auto-mounted to a mount point inside /tmp. Is that a normal thing for OpenWRT? I always thought in Linux /tmp is meant to be a temporary location which gets automatically cleaned often. Is it OK to leave it mounted at this location and use it for permanent files?

2

Let's see the output of the following:

ubus call system board
mount
df -h
3

And to answer this question... no, this is not 'normal' -- OpenWrt normally sets up tmp as a ramdisk, so external storage would not typically mount here. But obviously someone could have configured things differently. Or, maybe your device isn't running official OpenWrt. We'll know more based on the output I requested above.

4 
root@GL-AXT1800:~# ubus call system board
{
	"kernel": "4.4.60",
	"hostname": "GL-AXT1800",
	"system": "ARMv7 Processor rev 4 (v7l)",
	"model": "GL Technologies, Inc. AXT1800",
	"board_name": "glinet,axt1800",
	"rootfs_type": "squashfs",
	"release": {
		"distribution": "OpenWrt",
		"version": "21.02-SNAPSHOT",
		"revision": "r16399+159-c67509efd7",
		"target": "ipq807x/ipq60xx",
		"description": "OpenWrt 21.02-SNAPSHOT r16399+159-c67509efd7",
		"tip-revision": "OpenWrt 21.02-SNAPSHOT r16399+159-c67509efd7 / TIP-devel-d303bd39",
		"tip-version": "devel"
	}
}
root@GL-AXT1800:~# mount
mtd:ubi_rootfs on /rom type squashfs (ro,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,noatime)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,noatime)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noatime)
/dev/ubi0_2 on /overlay type ubifs (rw,noatime)
overlayfs:/overlay on / type overlay (rw,noatime,lowerdir=/,upperdir=/overlay/upper,workdir=/overlay/work)
tmpfs on /dev type tmpfs (rw,nosuid,relatime,size=512k,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
debugfs on /sys/kernel/debug type debugfs (rw,noatime)
bpffs on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,noatime,mode=700)
pstore on /sys/fs/pstore type pstore (rw,noatime)
/dev/mmcblk0p1 on /tmp/mountd/disk1_part1 type exfat (rw,relatime,fmask=0000,dmask=0000,allow_utime=177777,iocharset=utf8,errors=remount-ro)
nfsd on /proc/fs/nfsd type nfsd (rw,relatime)
root@GL-AXT1800:~# 
root@GL-AXT1800:~# df -h
Filesystem                Size      Used Available Use% Mounted on
mtd:ubi_rootfs           52.8M     52.8M         0 100% /rom
tmpfs                   196.4M    612.0K    195.8M   0% /tmp
/dev/ubi0_2              45.6M    148.0K     43.1M   0% /overlay
overlayfs:/overlay       45.6M    148.0K     43.1M   0% /
tmpfs                   512.0K         0    512.0K   0% /dev
/dev/mmcblk0p1           29.3G    320.0K     29.3G   0% /tmp/mountd/disk1_part1
5

Yup... this is not official OpenWrt. It's gl-inet's highly customized fork for a product that they built. Your device is not supported by the OpenWrt project.

You'll need to ask on the GL-inet forums or support channels since they have made significant and material changes to the way that OpenWrt functions -- it's a blackbox to us.

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