Recently I took over a few RHEL systems running with the native DM-multipath, which had been installed & configured by other persons.
My doubts focus on the following questions:
1). Why there would only a part of dm-? files from dm10~dm19 under the /dev directory
2). Why all the mapper files do not point to their corresponding
symbol link dm-? files
Note: but all the complete dm-? in the system kernel can still be seen from the /proc/partitions.
Despite these symptoms, all the systems running with the native DM-multipath can do work fine.
#
#
# ls -ltr /dev/mapper
total 0
crw------- 1 root root 10, 60 Jun 22 2021 control
brw-rw---- 1 root disk 253, 9 Jun 22 2021 vgroot-Lvswap
brw-rw---- 1 root disk 253, 10 Jun 22 2021 3600c0ff0001582e1dc40b45101000000
brw-rw---- 1 root disk 253, 17 Jun 22 2021 3600c0ff0001582e1bdaa115201000000
brw-rw---- 1 root disk 253, 13 Jun 22 2021 3600c0ff0001582e1bc43b45101000000
brw-rw---- 1 root disk 253, 16 Jun 22 2021 3600c0ff0001582e189aa115201000000
brw-rw---- 1 root disk 253, 12 Jun 22 2021 3600c0ff0001582e16641b45101000000
brw-rw---- 1 root disk 253, 15 Jun 22 2021 3600c0ff0001582e15bceba5101000000
brw-rw---- 1 root disk 253, 14 Jun 22 2021 3600c0ff0001582e13bceba5101000000
brw-rw---- 1 root disk 253, 11 Jun 22 2021 3600c0ff0001582e11141b45101000000
brw-rw---- 1 root disk 253, 18 Jun 22 2021 3600c0ff0001581c1ca81625501000000
brw-rw---- 1 root disk 253, 19 Jun 22 2021 3600c0ff0001581c1895b895901000000
brw-rw---- 1 root disk 253, 20 Jun 22 2021 vgoms-lvoms
brw-rw---- 1 root disk 253, 21 Jun 22 2021 vghes-lvhes
brw-rw---- 1 root disk 253, 22 Jun 22 2021 vgdata-lvoadata
brw-rw---- 1 root disk 253, 24 Jun 22 2021 vgdata-lvhnweb
brw-rw---- 1 root disk 253, 23 Jun 22 2021 vgdata-lvdocdata
brw-rw---- 1 root disk 253, 0 Jun 22 2021 vgroot-Lvroot
brw-rw---- 1 root disk 253, 1 Jun 22 2021 vgroot-Lvhome
brw-rw---- 1 root disk 253, 2 Jun 22 2021 vgroot-Lvvar
brw-rw---- 1 root disk 253, 3 Jun 22 2021 vgroot-Lvtmp
brw-rw---- 1 root disk 253, 4 Jun 22 2021 vgroot-Lvinstall
brw-rw---- 1 root disk 253, 5 Jun 22 2021 vgroot-Lvusr
brw-rw---- 1 root disk 253, 6 Jun 22 2021 vgroot-Lvopenv
brw-rw---- 1 root disk 253, 7 Jun 22 2021 vgroot-Lvapp
brw-rw---- 1 root disk 253, 8 Jun 22 2021 vgroot-Lvoracle
brw-rw---- 1 root disk 253, 25 Nov 23 17:24 vgqdisk-lvqdisk
#
#
#
# ls -l /dev/dm-*
brw-rw---- 1 root root 253, 10 Jun 22 2021 /dev/dm-10
brw-rw---- 1 root root 253, 11 Jun 22 2021 /dev/dm-11
brw-rw---- 1 root root 253, 12 Jun 22 2021 /dev/dm-12
brw-rw---- 1 root root 253, 13 Jun 22 2021 /dev/dm-13
brw-rw---- 1 root root 253, 14 Jun 22 2021 /dev/dm-14
brw-rw---- 1 root root 253, 15 Jun 22 2021 /dev/dm-15
brw-rw---- 1 root root 253, 16 Jun 22 2021 /dev/dm-16
brw-rw---- 1 root root 253, 17 Jun 22 2021 /dev/dm-17
brw-rw---- 1 root root 253, 18 Jun 22 2021 /dev/dm-18
brw-rw---- 1 root root 253, 19 Jun 22 2021 /dev/dm-19
#
#
#
# cat /proc/partitions
major minor #blocks name
104 0 292935982 cciss/c0d0
104 1 104391 cciss/c0d0p1
104 2 292824787 cciss/c0d0p2
8 0 976512 sda
8 16 97656192 sdb
8 32 97656192 sdc
8 48 97656192 sdd
8 64 97656192 sde
8 80 97656192 sdf
8 96 97656192 sdg
8 112 97656192 sdh
8 128 585937472 sdi
8 144 989858240 sdj
8 160 976512 sdk
8 176 97656192 sdl
8 192 97656192 sdm
8 208 97656192 sdn
8 224 97656192 sdo
8 240 97656192 sdp
65 0 97656192 sdq
65 16 97656192 sdr
65 32 585937472 sds
65 48 989858240 sdt
253 0 10485760 dm-0
253 1 5242880 dm-1
253 2 5242880 dm-2
253 3 5242880 dm-3
253 4 15728640 dm-4
253 5 10485760 dm-5
253 6 20971520 dm-6
253 7 20971520 dm-7
253 8 62914560 dm-8
253 9 16777216 dm-9
253 10 976512 dm-10
253 11 97656192 dm-11
253 12 97656192 dm-12
253 13 97656192 dm-13
253 14 97656192 dm-14
253 15 97656192 dm-15
253 16 97656192 dm-16
253 17 97656192 dm-17
253 18 585937472 dm-18
253 19 989858240 dm-19
253 20 989855744 dm-20
253 21 585105408 dm-21
253 22 209715200 dm-22
253 23 209715200 dm-23
253 24 209715200 dm-24
253 25 974848 dm-25
#
#
