After 24.04.1 Unable to mount (usb dev)

dagr2 · 25 September 2024 17:05

After running the update from 22.04 to 24.04 it no longer automatically mounts an USB hard drive that has been working properly for years. The drive is recognized as /dev/sdb1 and appears to attempt mounting at an incremented path instead of the original (/media/dagr2/WD500GB1 instead of /media/dagr2/WD500GB). It raises an "Unable to mount WD500GB" titled message with "Error mounting /dev/sdb1 at /media/dagr2/WD550GB1: wrong fs type, bad option, bad superblock on /dev/sdc1, missing codepage or helper program, or other error."

If I attempt to mount the drive manually, it succeeds (and the drive can be used without any issues).

sudo mount /dev/sdb1 /media/dagr2/WD500GB

I suspect there is a configuration file with an entry left from 22.04 that 24.04 is having an issue with. I've looked through several posts related to USB mounting issues, but I haven't found anything yet for this scenario.

Any thoughts or suggestions are welcome.

Bombilla · 25 September 2024 17:12

Hi, @dagr2 and welcome to the Ubuntu MATE Community!

ericmarceau · 25 September 2024 19:07

For auto-mounting to the desired directory, you must allow the auto-mounter to create that directory on demand, assuming "WD500GB" is your USB device's "Label".

You must first remove the directory, then attempt the automount by inserting your USB connection/disk.

Otherwise, you must create an entry in your fstab with all the necessary details, AND create the mount point directory, which will then be used because fstab directs it to be used.

--- edit ----
As Eugene said just below, UUID is what I use for all devices, not just USB devices. Here is my entry for an 8GB USB stick:

# /dev/sdc1    vfat     null       D4FB-FBCF                              28.9G         /media/userid/VERB_R_F1 USB_EXTERNAL
#UUID=29BF-35A0 		/media/userid/VERB_R_F1 	vfat 	rw,relatime,codepage=347,iocharset=iso8859-1,shortname=mixed,showexec,utf8,errors=remount-ro,uhelper=udisks2,nofail,noauto 	0 	0
UUID=29BF-35A0 		/media/userid/VERB_R_F1 	vfat 	user,owner,utf8,rw,suid,dev,umask=000,relatime,codepage=347,iocharset=iso8859-1,shortname=mixed,showexec,utf8,errors=remount-ro,uhelper=udisks2,nofail,noauto 	0 	0

The commented line was the system-assigned defaults. The bottome line is how I modified that for my needs.

ugnvs · 25 September 2024 19:09

May be, mounting drive by UUID would be reliable?

https://www.cyberciti.biz/faq/linux-finding-using-uuids-to-update-fstab/

dagr2 · 25 September 2024 19:34

I took the following steps/observations:

removed the directory WD500GB.
plugged the external drive (with label WD500GB) back into the USB port.
Watched the /media/dagr2/ folder where a new folder appeared for a split second, disappeared, and then the "Unable to mount" message displayed.

If I go the route of explicitly defining the UUID in my fstab, should I be using the actual UUID or the PARTUUID from this response:

$ sudo blkid /dev/sdb1
/dev/sdb1: LABEL="WD500GB" BLOCK_SIZE="512" UUID="3D9E7FE16565DC4F" TYPE="ntfs" PARTUUID="4c033b70-01"

ericmarceau · 25 September 2024 19:37

Only use UUID, never PARTUUID.

If you use

lsblk -P -p -o NAME,FSTYPE,PARTLABEL,UUID,SIZE,MOUNTPOINT,SUBSYSTEMS

you will see that they are different.

If you want a general utility for reporting such details formatted for direct use into the fstab, here is a script that I created for that, among other things.

Script Devices__ReportDiskParts.sh:

#!/bin/sh

#23456789+123456789+123456789+123456789+123456789+123456789+123456789+123456789+123456789+123456789+
####################################################################################################
###
###	$Id: Devices__ReportDiskParts.sh,v 1.7 2021/02/20 02:43:37 root Exp root $
###
###	Script to report all partitions that detected by the system.
###
####################################################################################################

TMP=/tmp/`basename $0 ".sh" `.tmp

doFSTAB=0
while [ $# -gt 0 ]
do
	case $1 in
		"--fstab" )	doFSTAB=1 ; break ;;
		"--disk" )	lsblk -l -p --output-all | awk  '/[/]dev[/]sd[a-z][0-9]/ { print $0 }' | sort --key=3 | awk '{ printf("%s\n\n", $0 ) ; }' ; exit 0 ;;
		"--pairs" )	lsblk -p -P --output-all | awk  '/[/]dev[/]sd[a-z][0-9]/ { print $0 }' | sort --key=3 | awk '{ printf("%s\n\n", $0 ) ; }' ; exit 0 ;;
		"--raw" )	lsblk -l -p --output-all | sort --key=3 | awk '{ printf("%s\n\n", $0 ) ; }' ; exit 0 ;;
		* )  echo "\n\t Invalid parameter '$1' used on command line.  Only options allowed:  [ --raw | --disk | --fstab ]\n Bye!\n" ; exit 1 ;;
	esac
done

if [ -z "${MROOT}" ]
then
	MROOT="/site" ; export MROOT
fi

pROOT=`df / | grep '/dev/' | awk '{ print $1 }' `
dROOT=`echo ${pROOT} | cut -c1-8 `

# If not terminal redirect comments to stderr.
if [   -t 1 ] ; then echo "\n\t NOTE:  Expected mount point parent for all partitions not on root device => '$MROOT' ..."   ; fi
#if [ ! -t 1 ] ; then echo "\n\t NOTE:  Expected mount point parent for all partitions not on root device => '$MROOT' ..." >&2 ; fi

###
###	All available parameters for lsblk	(based on lsblk from util-linux 2.31.1)
###
###	In sort order reported by --output-all
###
#1	 NAME
#	 KNAME
#	 MAJ:MIN
#2	 FSTYPE
#5	 MOUNTPOINT
#ALT3	 LABEL
#4	 UUID
#	 PARTTYPE
#3	 PARTLABEL
#	 PARTUUID
#	 PARTFLAGS
#	 RA
#	 RO
#	 RM
#	 HOTPLUG
#	 MODEL
#	 SERIAL
#6	 SIZE
#	 STATE
#	 OWNER
#	 GROUP
#	 MODE
#	 ALIGNMENT
#	 MIN-IO
#	 OPT-IO
#	 PHY-SEC
#	 LOG-SEC
#	 ROTA
#	 SCHED
#	 RQ-SIZE
#	 TYPE
#	 DISC-ALN
#	 DISC-GRAN
#	 DISC-MAX
#	 DISC-ZERO
#	 WSAME
#	 WWN
#	 RAND
#	 PKNAME
#	 HCTL
#	 TRAN
#7	 SUBSYSTEMS
#	 REV
#	 VENDOR
#	 ZONED


#lsblk -l -p -o NAME,FSTYPE,PARTLABEL,UUID,SIZE,MOUNTPOINT,SUBSYSTEMS | grep -v 'GRUB' | awk  '/[/]dev[/]sd[a-z][0-9]/ { print $0 }' | sort --key=3 > ${TMP}.lsblk
#cat ${TMP}.lsblk
#cat ${TMP}.lsblk | awk '{ print NF }'

lsblk -P -p -o NAME,FSTYPE,PARTLABEL,UUID,SIZE,MOUNTPOINT,SUBSYSTEMS | grep -v 'GRUB' | awk  '/[/]dev[/]sd[a-z][0-9]/ { print $0 }' | sort --key=3 > ${TMP}.lsblk.PAIRS

#cat ${TMP}.lsblk.PAIRS
while read line
do
	eval echo '${line}' | tr ' ' "\n" |
	{	fTYPE=""
		while read data
		do
			eval echo '${data}' | awk -F'"' -v ftype="${fTYPE}" '{
				split($1, vars, "=" ) ;
				Fname=vars[1] ;
#				Fval=vars[2] ;	
				Fval=$2 ;	
				if( Fval == "" ){
					Fval="null" ;
				} ;
				printf("%s ", Fval) ;
#				printf("%s|%s ", Fname, Fval) ;
			}'
#			case ${data} in
#				FSTYPE* ) fTYPE="USB" ;;
#				* ) ;;
#			esac
		done
	}
	echo ""
done <${TMP}.lsblk.PAIRS >${TMP}.lsblk
#cat ${TMP}.lsblk
#cat ${TMP}.lsblk | awk '{ print NF }'


## WD 4 TB My Book
#----------------------------------------------------------------------------------------------------------------------
#/dev/sdb1 on /site/My Book type exfat (rw,nosuid,nodev,relatime,uid=1000,gid=1000,fmask=0022,dmask=0022,iocharset=utf8,namecase=0,errors=remount-ro,uhelper=udisks2)
###	1,4,9,7,5,18
#----------------------------------------------------------------------------------------------------------------------
###	/dev/sdb1    exfat    My         Book                                   Not_Mounted   /My
#/dev/sdb1  /dev/sdb1  /dev/sdb1    8:17     3.7T   3.7T exfat        6M     0% /site/My Book     My Book  40FA-E56B                            fc843c51-1aec-4aab-8676-9043c9e59d0d atari  ebd0a0a2-b9e5-4433-87c0-68b6b72699c7 My Book   4c1ee663-135c-4809-a61e-f38ec52d80a7           128  0  0       1                                                  3.7T         root  disk  brw-rw----         0   4096      0    4096     512    1 mq-deadline       2 part        0        4K       4G         0    0B                       1 /dev/sdb                   block:scsi:usb:pci               none
#----------------------------------------------------------------------------------------------------------------------
###	/dev/sde3    ext4     DB002_F1   1b4157be-79cd-472b-96d9-a4cabacaffe1   Not_Mounted   /site/DB002_F1
#/dev/sde3  /dev/sde3  /dev/sde3    8:67                 ext4                                                 DB002_F1 1b4157be-79cd-472b-96d9-a4cabacaffe1 9a3649a5-cbbb-4f1b-ae0b-f3c0d9cdec21 dos    c12a7328-f81f-11d2-ba4b-00a0c93ec93b DB002_F1  a9b2eda8-ec21-4999-b1f6-eab36ce3bf75           128  0  0       0                                                279.4G         root  disk  brw-rw----         0   4096      0    4096     512    1 mq-deadline      64 part        0        0B       0B         0    0B 0x50014ee263b2c636    1 /dev/sde                   block:scsi:pci                   none
#----------------------------------------------------------------------------------------------------------------------


#----------------------------------------------------------------------------------------------------------------------
###	**** ERROR ****  Not handling 'My Passport' condition correctly
###
###	Reporting as follows:
###	/dev/sde1    ntfs     My         null                                   Mounted       1.8T                           /media/ericthered/My
#----------------------------------------------------------------------------------------------------------------------

if [ ${doFSTAB} -eq 0 ]
then
	if [   -t 1 ] ; then echo "\n\t ALL recognized DISK partitions:\n"     ; fi
	#if [ ! -t 1 ] ; then echo "\n\t ALL recognized DISK partitions:\n" >&2 ; fi

	cat ${TMP}.lsblk | awk -v othrPath=${MROOT} -v dROOT="${dROOT}" '{
		if ( $6 == "null" ){
			if ( $2 == "swap" ){
			       	printf("%-12s %-8s %-10s %-38s %-13s %-30s %s\n", $1, $2, $3, $4, "Not_Enabled", "[SWAP_OFFLINE]", $7 ) ;  
			}else{
				if ( index($1,dROOT) == 0 ){
					thatPath=sprintf("%s/%s", othrPath, $3 ) ;
					printf("%-12s %-8s %-10s %-38s %-13s %-30s %s\n", $1, $2, $3, $4, "Not_Mounted", thatPath, $7 ) ; 
				}else{
					thatPath=sprintf("/%s", $3 ) ;
					printf("%-12s %-8s %-10s %-38s %-13s %-30s %s\n", $1, $2, $3, $4, "Not_Mounted", thatPath, $7 ) ; 
				} ;
			} ;
		}else{
	     		if ( $2 == "swap" ){
				printf("%-12s %-8s %-10s %-38s %-13s %-30s %s\n", $1, $2, $3, $4, "Enabled", $6, $7 ) ;
			}else{
				printf("%-12s %-8s %-10s %-38s %-13s %-30s %s\n", $1, $2, $3, $4, "Mounted", $6, $7 ) ;
			} ;
		} ;
	}'
else
	if [   -t 1 ] ; then echo "\n\t ALL recognized DISK partitions reported in format required to update '/etc/fstab':\n"     ; fi
	#if [ ! -t 1 ] ; then echo "\n\t ALL recognized DISK partitions reported in format required to update '/etc/fstab':\n" >&2 ; fi

	#/dev/sdd1    ext4     DB002_F1   0aa50783-954b-4024-99c0-77a2a54a05c2   300G          /site/DB002_F1
	#UUID=f56b6086-229d-4c17-8a5b-e68de1a4e73d	/	ext4	errors=remount-ro	0	1
	#UUID=7e9a663e-ff1d-4730-8544-c37519056b6f	/DB001_F2	ext4	nosuid,nodev,nofail,errors=remount-ro	0	2 
	#UUID=c37e53cd-5882-401c-8ba3-172531a082e9	none	swap	sw,pri=3	0	0

	###
	###	FUTURES:   USB options  rw,suid,umask=0000,uid=1000,gid=1000
	###
	cat ${TMP}.lsblk | awk -v othrPath=${MROOT} -v pROOT="${pROOT}" -v dROOT="${dROOT}" '{
	     if( index( $0, "usb" ) != 0 ){
			usbPlug="USB_EXTERNAL" ;
	     }else{
			usbPlug="INTERNAL" ;
	     } ;

		if ( $6 == "null" ){
			if ( $2 == "swap" ){
				if ( $1 == pROOT ) {
					perms="sw,pri=1" ;
					seq=1 ;
				}else{
					perms="sw,pri=2" ;
					seq=2 ;
				} ;
				if( $4 == "null" ){
					printf("### %s ###  No value for UUID. No file system on this partition.\n\n", $3 ) ;
				}else{
					printf("# %-12s %-8s %-10s %-38s %-13s %s %s\n", $1, $2, $3, $4, $5, "[SWAP]", usbPlug ) ;  
					printf("UUID=%s \t%s \t%s \t%s \t%s \t%s\n\n", $4, "none", $2, perms, "0", seq ) ;
				} ;
			}else{
				if ( $1 == pROOT ) {
					perms="defaults" ;
					seq=0 ;
				}else{
					#perms="nosuid,nodev,nofail,defaults" ;
					if( usbPlug == "USB_EXTERNAL" ){
						perms="defaults,nofail,noauto" ;
					}else{
						perms="defaults,nofail" ;
					} ;
					if ( $1 ~ dROOT ) { seq=1 ; }else{ seq=2 ; } ;
				} ;
				if( $4 == "null" ){
					printf("### %s ###  No value for UUID. No file system on this partition.\n\n", $3 ) ;
				}else{
					if ( index($1,dROOT) == 0 ){
						printf("# %-12s %-8s %-10s %-38s %-13s %s/%s %s\n", $1, $2, $3, $4, $5, othrPath, $3, usbPlug ) ; 
						printf("UUID=%s \t%s/%s \t%s \t%s \t%s \t%s\n\n", $4, othrPath, $3, $2, perms, "0", seq ) ;
					}else{
						printf("# %-12s %-8s %-10s %-38s %-13s /%s %s\n", $1, $2, $3, $4, $5, $3, usbPlug ) ; 
						printf("UUID=%s \t/%s \t%s \t%s \t%s \t%s\n\n", $4, $3, $2, perms, "0", seq ) ;
					} ;
				} ;
			} ;
		}else{
	     		if ( $2 == "swap" ){

				if ( $1 == pROOT ) {
					perms="sw,pri=1" ;
					seq=1 ;
				}else{
					perms="sw,pri=2" ;
					seq=2 ;
				} ;
				if( $4 == "null" ){
					printf("### %s ###  No value for UUID. No file system on this partition.\n\n", $3 ) ;
				}else{
					printf("# %-12s %-8s %-10s %-38s %-13s %s %s\n", $1, $2, $3, $4, $5, $6, usbPlug ) ;
					printf("UUID=%s \t%s \t%s \t%s \t%s \t%s\n\n", $4, "none", $2, perms, "0", seq ) ;
				};
			}else{

				if ( $1 == pROOT ) {
					perms="defaults" ;
					seq=0 ;
				}else{
					#perms="nosuid,nodev,nofail,defaults" ;
					if( usbPlug == "USB_EXTERNAL" ){
						perms="defaults,nofail,noauto" ;
					}else{
						perms="defaults,nofail" ;
					} ;
					if ( $1 ~ dROOT ) { seq=1 ; }else{ seq=2 ; } ;
				} ;
				if( $4 == "null" ){
					printf("### %s ###  No value for UUID. No file system on this partition.\n\n", $3 ) ;
				}else{
					printf("# %-12s %-8s %-10s %-38s %-13s %s %s\n", $1, $2, $3, $4, $5, $6, usbPlug ) ;
					printf("UUID=%s \t%s \t%s \t%s \t%s \t%s\n\n", $4, $6, $2, perms, "0", seq ) ;
				};
			} ;
		} ;
	}'
fi

# Other command format for other properties related to partitions:
#	lsblk -o NAME,ALIGNMENT,MIN-IO,OPT-IO,PHY-SEC,LOG-SEC,ROTA,SCHED,RQ-SIZE,RA,WSAME

# Other option which is not as complete:
#	blkid -o list

if [   -t 1 ] ; then echo "\n\t Done.  [`basename $0 `]\n"     ; fi
#if [ ! -t 1 ] ; then echo "\t Done.  [`basename $0 `]\n" >&2 ; fi

rm -f ${TMP}.*

exit 0
exit 0
exit 0

NOTE: I assign a non-default mountpoint using that script. That non-default mountpoint BLOCKS attempts at automounting. You can modify that (replace "/site" with "/media/userid") to suit your needs, either by tweaking the outputs, or modifying the script directly to suit your own defaults.

With no parameters, the report looks like this:

	 NOTE:  Expected mount point parent for all partitions not on root device => '/site' ...

	 ALL recognized DISK partitions:

/dev/sda3    ext4     DB001_F1   5dcf1a96-fa2e-42f5-9a08-37fcce0f0878   Mounted       /                              block:scsi:pci
/dev/sda7    ext4     DB001_F2   7e9a663e-ff1d-4730-8544-c37519056b6f   Mounted       /DB001_F2                      block:scsi:pci
/dev/sda8    ext4     DB001_F3   4f7d4192-b136-4a94-b06b-736f76155816   Mounted       /DB001_F3                      block:scsi:pci
/dev/sda9    ext4     DB001_F4   7f37ffd4-779a-46c6-b440-f384fb75eb98   Mounted       /DB001_F4                      block:scsi:pci
/dev/sda12   ext4     DB001_F5   14e15125-6c47-499e-b1a9-734a0f928b5e   Mounted       /DB001_F5                      block:scsi:pci
/dev/sda13   ext4     DB001_F6   0d416936-e091-49a7-9133-b8137d327ce0   Mounted       /DB001_F6                      block:scsi:pci
/dev/sda14   ext4     DB001_F7   c2ff9e15-b50e-4c56-9c03-918bf81e0ab5   Mounted       /DB001_F7                      block:scsi:pci
/dev/sda4    ext4     DB001_F8   46fcb33d-5f0d-423b-b6a7-512c58c76aba   Mounted       /DB001_F8                      block:scsi:pci
/dev/sda2    swap     DB001_S1   266efd3e-f04d-4ea3-89e6-45e6ac227fa1   Not_Enabled   [SWAP_OFFLINE]                 block:scsi:pci
/dev/sda10   swap     DB001_S2   3b9a2c7a-67d4-4de7-ae66-214937dc47f4   Enabled       [SWAP]                         block:scsi:pci
/dev/sda11   swap     DB001_S3   78b04c8c-8ace-4b46-817d-7059aa1668b7   Enabled       [SWAP]                         block:scsi:pci
/dev/sdb1    ext4     null       02c997f5-6b98-4c0a-9179-a8b89bfeb8f3   Not_Mounted   /site/null                     block:scsi:pci
/dev/sdb2    swap     null       b9aa2a71-9430-4011-a955-9451d7f2c421   Enabled       [SWAP]                         block:scsi:pci

	 Done.  [Devices__ReportDiskParts.sh]

With the "--fstab" parameter, it looks like this:

	 NOTE:  Expected mount point parent for all partitions not on root device => '/site' ...

	 ALL recognized DISK partitions reported in format required to update '/etc/fstab':

# /dev/sda3    ext4     DB001_F1   5dcf1a96-fa2e-42f5-9a08-37fcce0f0878   195.3G        / INTERNAL
UUID=5dcf1a96-fa2e-42f5-9a08-37fcce0f0878 	/ 	ext4 	defaults 	0 	0

# /dev/sda7    ext4     DB001_F2   7e9a663e-ff1d-4730-8544-c37519056b6f   293G          /DB001_F2 INTERNAL
UUID=7e9a663e-ff1d-4730-8544-c37519056b6f 	/DB001_F2 	ext4 	defaults,nofail 	0 	1

# /dev/sda8    ext4     DB001_F3   4f7d4192-b136-4a94-b06b-736f76155816   293G          /DB001_F3 INTERNAL
UUID=4f7d4192-b136-4a94-b06b-736f76155816 	/DB001_F3 	ext4 	defaults,nofail 	0 	1

# /dev/sda9    ext4     DB001_F4   7f37ffd4-779a-46c6-b440-f384fb75eb98   293G          /DB001_F4 INTERNAL
UUID=7f37ffd4-779a-46c6-b440-f384fb75eb98 	/DB001_F4 	ext4 	defaults,nofail 	0 	1

# /dev/sda12   ext4     DB001_F5   14e15125-6c47-499e-b1a9-734a0f928b5e   195.3G        /DB001_F5 INTERNAL
UUID=14e15125-6c47-499e-b1a9-734a0f928b5e 	/DB001_F5 	ext4 	defaults,nofail 	0 	1

# /dev/sda13   ext4     DB001_F6   0d416936-e091-49a7-9133-b8137d327ce0   195.3G        /DB001_F6 INTERNAL
UUID=0d416936-e091-49a7-9133-b8137d327ce0 	/DB001_F6 	ext4 	defaults,nofail 	0 	1

# /dev/sda14   ext4     DB001_F7   c2ff9e15-b50e-4c56-9c03-918bf81e0ab5   293G          /DB001_F7 INTERNAL
UUID=c2ff9e15-b50e-4c56-9c03-918bf81e0ab5 	/DB001_F7 	ext4 	defaults,nofail 	0 	1

# /dev/sda4    ext4     DB001_F8   46fcb33d-5f0d-423b-b6a7-512c58c76aba   93.5G         /DB001_F8 INTERNAL
UUID=46fcb33d-5f0d-423b-b6a7-512c58c76aba 	/DB001_F8 	ext4 	defaults,nofail 	0 	1

# /dev/sda2    swap     DB001_S1   266efd3e-f04d-4ea3-89e6-45e6ac227fa1   1G            [SWAP] INTERNAL
UUID=266efd3e-f04d-4ea3-89e6-45e6ac227fa1 	none 	swap 	sw,pri=2 	0 	2

# /dev/sda10   swap     DB001_S2   3b9a2c7a-67d4-4de7-ae66-214937dc47f4   996.2M        [SWAP] INTERNAL
UUID=3b9a2c7a-67d4-4de7-ae66-214937dc47f4 	none 	swap 	sw,pri=2 	0 	2

# /dev/sda11   swap     DB001_S3   78b04c8c-8ace-4b46-817d-7059aa1668b7   996.2M        [SWAP] INTERNAL
UUID=78b04c8c-8ace-4b46-817d-7059aa1668b7 	none 	swap 	sw,pri=2 	0 	2

# /dev/sdb1    ext4     null       02c997f5-6b98-4c0a-9179-a8b89bfeb8f3   463.8G        /site/null INTERNAL
UUID=02c997f5-6b98-4c0a-9179-a8b89bfeb8f3 	/site/null 	ext4 	defaults,nofail 	0 	2

# /dev/sdb2    swap     null       b9aa2a71-9430-4011-a955-9451d7f2c421   2G            [SWAP] INTERNAL
UUID=b9aa2a71-9430-4011-a955-9451d7f2c421 	none 	swap 	sw,pri=2 	0 	2


	 Done.  [Devices__ReportDiskParts.sh]

dagr2 · 25 September 2024 20:00

Perfect. RESOLVED.

Thank you both (@ericmarceau and @ugnvs) for the assistance!
Between your examples and the reference material link, I was able to get my external USB drive to automount again, with the following steps:

Used blkid to get the UUID value for /dev/sdb1

sudo blkid /dev/sdb1
/dev/sdb1: LABEL="WD500GB" BLOCK_SIZE="512" UUID="3E9E7FE16565DC4F" TYPE="ntfs" PARTUUID="4c03370-01"

Add an entry to /etc/fstab for that device

sudo nano /etc/fstab

# added to the bottom of the file:
# Manual entry for WD500GB external USB drive 
UUID=3D9E7FD16565DC4F    /media/dagr2/WD500GB    ntfs    defaults,errors=remount-ro 0    1

Thanks to @Bombilla for the welcome, too.