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To check all of the block devices to see if any of them are ≤ 4096 use the following grep.
[robm@robm-rhel7 ~]$ grep [0-9] /sys/block/sd*/queue/max_sectors_kb /sys/block/sda/queue/max_sectors_kb:512 /sys/block/sdb/queue/max_sectors_kb:4096 /sys/block/sdc/queue/max_sectors_kb:4096 /sys/block/sdd/queue/max_sectors_kb:4096 /sys/block/sde/queue/max_sectors_kb:4096 /sys/block/sdf/queue/max_sectors_kb:4096 /sys/block/sdg/queue/max_sectors_kb:4096 /sys/block/sdh/queue/max_sectors_kb:4096 /sys/block/sdi/queue/max_sectors_kb:4096 -
Next review run the following command and search for the block device sd* that is set wrong and verify it is on a FlashArray volume.
[root@robm-rhel7 robm]# multipath -ll Feb 19 13:13:34 | /etc/multipath.conf line 97, duplicate keyword: defaults 3624a93702bcee22e6c784a32000b9b28 dm-9 PURE ,FlashArray size=600G features='0' hwhandler='0' wp=rw `-+- policy='queue-length 0' prio=50 status=active |- 6:0:10:3 sdj 8:144 active ready running |- 6:0:13:3 sdk 8:160 active ready running |- 7:0:8:3 sdl 8:176 active ready running `- 7:0:9:3 sdm 8:192 active ready running 3624a93702bcee22e6c784a32000b99d3 dm-3 PURE ,FlashArray size=350G features='0' hwhandler='0' wp=rw `-+- policy='queue-length 0' prio=50 status=active |- 6:0:10:1 sdf 8:80 active ready running |- 6:0:13:1 sdh 8:112 active ready running |- 7:0:8:1 sdb 8:16 active ready running `- 7:0:9:1 sdd 8:48 active ready runningsda is the host local boot block device.
If the value is ≤ 4096, then no action is necessary. However, if this value is > 4096, we recommend that you change the max to 4096.