6TB storage expansion - Revision history

Jw297: /* Breakthrough */

2018-11-19T11:48:04Z

‎Breakthrough

Rf at 15:19, 29 June 2016

2016-06-29T15:19:09Z

Rf at 15:05, 29 June 2016

2016-06-29T15:05:22Z

Rf at 14:37, 29 June 2016

2016-06-29T14:37:35Z

Rf at 14:28, 29 June 2016

2016-06-29T14:28:05Z

Rf at 13:54, 29 June 2016

2016-06-29T13:54:36Z

Rf at 13:50, 29 June 2016

2016-06-29T13:50:46Z

Rf at 13:48, 29 June 2016

2016-06-29T13:48:30Z

Rf at 13:42, 29 June 2016

2016-06-29T13:42:04Z

Rf at 13:38, 29 June 2016

2016-06-29T13:38:55Z

@@ Line 187: / Line 187: @@
 Here is the raw recipe:
-  # echo 1 > /sys/block/device_name/device/rescan
+  # echo 1 > /sys/block/<device_name>/device/rescan
   # multipathd -k'resize map mpatha'

@@ Line 231: / Line 231: @@
 = Links=
 * [https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html-single/DM_Multipath/ Red Hat DM-Multipath guide]
 * [https://help.ubuntu.com/lts/serverguide/multipath-admin-and-troubleshooting.html ubuntu troubleshooting guide to DM-Multipath]
 * [http://kb.kristianreese.com/index.php?View=entry&EntryID=127 Kristian Reese's LUN solution]

← Older revision		Revision as of 15:05, 29 June 2016
Line 201:		Line 201:

	The next thing that has to be done is extend the logical volumes and grow the XFS.		The next thing that has to be done is extend the logical volumes and grow the XFS.
		+
		+	== LVM ==
		+	A quick '''pvscan''' will reveal that the '''/dev/mapper/mpathd''' device has no free space on it. So the extra 6TB has not been recognised? Well, it's because the PV needs to be resized. This can be done with:
		+
		+	pvresize /dev/mapper/mpathd
		+
		+	This will show how one PV was resized and 0 were not changed (unusually phrased message), and a quick pvscan will show that the PV now has 6TB extra space. Next up is the logical volume .. this must be extended into newly resized PV. This is done with the follwong command:
		+
		+	lvextend /dev/STORAGE/storage /dev/mapper/mpathd
		+
		+	== XFS ==
		+
		+	xfs is very easy to resize and can famously be done while filesystem is already mounted.
		+
		+	xfs_growfs /dev/STORAGE/storage
		+
		+	This command returned extremely quickly and showed that the filesystem had been resize from 50T to 56T. Mission accomplished!
		+
		+	= Summary of successful operation =
		+
		+	echo 1 > /sys/block/sdd/device/rescan
		+	echo 1 > /sys/block/sde/device/rescan
		+	echo 1 > /sys/block/sdf/device/rescan
		+	echo 1 > /sys/block/sdg/device/rescan
		+	multipathd -k'resize map mpathd'
		+	pvresize /dev/mapper/mpathd
		+	lvextend /dev/STORAGE/storage /dev/mapper/mpathd
		+	xfs_growfs /dev/STORAGE/storage

	= Links=		= Links=

@@ Line 190: / Line 190: @@
   # multipathd -k'resize map mpatha'
-The realisation is that the device name is not dm-6, and there is more than one. I.e. the sd{d,e,f,g} mentioned in the "multipath -l" command are the devices.
+The realisation is that the device name is not '''dm-6''', and there could be more than one device. Namely, the sd{d,e,f,g} mentioned in the "multipath -l" command are the referred-to ''devices''. This becomes clear when we see that each have a '''device/rescan''' file which is write-only (we noted above that dm-6 has no such directory nor file). Also, attempts to create such a path/rescan directory and file in '''/sys/block/dm-6''' were fruitless. Therefore '''1''' wa echo'd to each of the four '''rescan''' files in the '''device''' subdirectory of '''/sys/block/sd{d,e,f,g}'''
 = Links=

← Older revision		Revision as of 14:28, 29 June 2016
Line 183:		Line 183:

	Other sites repeat the recipe ad nauseam. There is no mention about whether this can in fact be done live.		Other sites repeat the recipe ad nauseam. There is no mention about whether this can in fact be done live.
		+
		+	== Breakthrough ==
		+
		+	Here is the raw recipe:
		+	# echo 1 > /sys/block/device_name/device/rescan
		+	# multipathd -k'resize map mpatha'
		+
		+	The realisation is that the device name is not dm-6, and there is more than one. I.e. the sd{d,e,f,g} mentioned in the "multipath -l" command are the devices.
		+	This is clear because each have a '''device/rescan''' file which is write-only. Also attempt to create such a path/rescan in dm-6 were fruitless. Therefore '''1''' wa echo'd to each of the four '''rescan''' files in the '''device''' subdirectory of '''/sys/block/sd{d,e,f,g}'''
		+
		+

@@ Line 113: / Line 113: @@
   to: Direct-Access      Model: Compellent Vol   Rev: 0602
         Type:   Direct-Access                    ANSI SCSI revision: 05
   sg10 changed: device 6 0 1 1 ...
@@ Line 173: / Line 172: @@
 Despite some mentions of changed devices, the final summary is of no changes.
 = Procedure =

@@ Line 108: / Line 108: @@
   Scanning host 5 for  SCSI target IDs  0 1 2 3 4 5 6 7, all LUNs
   Scanning host 6 for  all SCSI target IDs, all LUNs
   sg7 changed:  device 6 0 0 1 ...
   from:Direct-Access                     : 01

← Older revision		Revision as of 13:48, 29 June 2016
Line 94:		Line 94:
	There is a relationship to the "multipath -l" output in terms of the vendor and model.		There is a relationship to the "multipath -l" output in terms of the vendor and model.

		+	There is also a rescan tool for SCSI
		+
		+	rescan-scsi-bus.sh
		+
		+	Out put is a bit voluminous, but here goes:
		+
		+	Scanning SCSI subsystem for new devices
		+	Scanning host 0 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 1 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 2 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 3 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 4 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 5 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	Scanning host 6 for all SCSI target IDs, all LUNs
		+	sg7 changed: device 6 0 0 1 ...
		+	from:Direct-Access : 01
		+	to: Direct-Access Model: Compellent Vol Rev: 0602
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+
		+	sg10 changed: device 6 0 1 1 ...
		+	from:Direct-Access : 01
		+	to: Direct-Access Model: Compellent Vol Rev: 0602
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	Scanning host 7 for all SCSI target IDs, all LUNs
		+	sg8 changed: device 7 0 1 1 ...
		+	from:Direct-Access : 01
		+	to: Direct-Access Model: Compellent Vol Rev: 0602
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	sg9 changed: device 7 0 2 1 ...
		+	from:Direct-Access : 01
		+	to: Direct-Access Model: Compellent Vol Rev: 0602
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	Scanning host 8 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	sg2 changed: device 8 0 10 0 ...
		+	from:Enclosure : 00
		+	to: Enclosure Model: SAS 6G Expander Rev: 0b05
		+	Type: Enclosure ANSI SCSI revision: 05
		+
		+	sg3 changed: device 8 0 11 0 ...
		+	from:Enclosure : 00
		+	to: Enclosure Model: SAS 6G Expander Rev: 0b05
		+	Type: Enclosure ANSI SCSI revision: 05
		+
		+	sg0 changed: device 8 0 8 0 ...
		+	from:Enclosure : 00
		+	to: Enclosure Model: SAS 6G Expander Rev: 0b05
		+	Type: Enclosure ANSI SCSI revision: 05
		+
		+	sg1 changed: device 8 0 9 0 ...
		+	from:Enclosure : 00
		+	to: Enclosure Model: SAS 6G Expander Rev: 0b05
		+	Type: Enclosure ANSI SCSI revision: 05
		+
		+	sg4 changed: device 8 2 0 0 ...
		+	from:Direct-Access : 00
		+	to: Direct-Access Model: MR9286-8e Rev: 3.29
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	Scanning host 9 for SCSI target IDs 0 1 2 3 4 5 6 7, all LUNs
		+	sg5 changed: device 9 2 0 0 ...
		+	from:Direct-Access : 00
		+	to: Direct-Access Model: MR9261-8i Rev: 2.13
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	sg6 changed: device 9 2 1 0 ...
		+	from:Direct-Access : 00
		+	to: Direct-Access Model: MR9261-8i Rev: 2.13
		+	Type: Direct-Access ANSI SCSI revision: 05
		+
		+	0 new or changed device(s) found.
		+	0 remapped or resized device(s) found.
		+	0 device(s) removed.
		+
		+	Despite some mentions of changed devices, the final summary is of no changes.
	= Procedure =		= Procedure =

@@ Line 3: / Line 3: @@
 instead of 50TB are now available for the bioinformatics cluster. The tasks required to realize this extra space are:
 * rescan multipath, details: multipath WWID; 36000d3100051f800000000000000016e (on mpathd)
 = Tools =
@@ Line 92: / Line 91: @@
     Vendor: COMPELNT Model: Compellent Vol   Rev: 0602
     Type:   Direct-Access                    ANSI  SCSI revision: 05
 = Procedure =

@@ Line 56: / Line 56: @@
   cat /proc/scsi/scsi
-−
   Attached devices:
   Host: scsi8 Channel: 00 Id: 08 Lun: 00