75 lines
1.4 KiB
Text
75 lines
1.4 KiB
Text
= Infrastructure/SOP/Raid Mismatch Count
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What to do when a raid device has a mismatch count
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== Contents
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[arabic]
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. Contact Information
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. Description
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. Correction
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____
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[arabic]
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. Step 1
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. Step 2
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____
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== Contact Information
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Owner::
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Fedora Infrastructure Team
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Contact::
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#fedora-admin, sysadmin-main
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Location::
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All
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Servers::
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Physical hosts
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Purpose::
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Provides database connection to many of our apps.
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== Description
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In some situations a raid device may indicate there is a count mismatch
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as listed in:
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....
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/sys/block/mdX/md/mismatch_cnt
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....
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Anything other than 0 is considered not good. Though if the number is
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low it's probably nothing to worry about. To correct this situation try
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the directions below.
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== Correction
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More than anything these steps are to A) Verify there is no problem and
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B) make the error go away. If step 1 and step 2 don't correct the
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problems, PROCEED WITH CAUTION. The steps below, however, should be
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relatively safe.
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Issue a repair (replace mdX with the questionable raid device):
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....
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echo repair > /sys/block/mdX/md/sync_action
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....
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Depending on the size of the array and disk speed this can take a while.
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Watch the progress with:
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....
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cat /proc/mdstat
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....
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Issue a check. It's this check that will reset the mismatch count if
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there are no problems. Again replace mdX with your actual raid device.:
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....
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echo check > /sys/block/mdX/md/sync_action
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....
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Just as before, you can watch the progress with:
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....
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cat /proc/mdstat
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....
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