When Adding a New Disk

echo "- - -" > /sys/class/scsi_host/host1/scan
echo "- - -" > /sys/class/scsi_host/host2/scan
echo "- - -" > /sys/class/scsi_host/host3/scan
echo "- - -" > /sys/class/scsi_host/host4/scan
echo "- - -" > /sys/class/scsi_host/host5/scan
echo "- - -" > /sys/class/scsi_host/host6/scan
echo "- - -" > /sys/class/scsi_host/host7/scan
echo "- - -" > /sys/class/scsi_host/host8/scan
echo "- - -" > /sys/class/scsi_host/host9/scan
echo "- - -" > /sys/class/scsi_host/host10/scan
echo "- - -" > /sys/class/scsi_host/host11/scan
echo "- - -" > /sys/class/scsi_host/host12/scan
echo "- - -" > /sys/class/scsi_host/host13/scan
echo "- - -" > /sys/class/scsi_host/host14/scan
echo "- - -" > /sys/class/scsi_host/host15/scan
echo "- - -" > /sys/class/scsi_host/host16/scan
echo "- - -" > /sys/class/scsi_host/host17/scan
echo "- - -" > /sys/class/scsi_host/host18/scan
echo "- - -" > /sys/class/scsi_host/host19/scan
echo "- - -" > /sys/class/scsi_host/host20/scan

When Increasing Existing Disk Size

echo "1" > /sys/class/block/sdX/device/rescan 

..where X is the device you increased and want to rescan.

maltipath

產生預設 maltipath 設定檔

mpathconf --enable --user_friendly_names y --find_multipaths y


config file
/etc/multipath.conf

服務重啟
systemctl restart multipathd


顯示路徑
multipath -ll

重新搜尋
multipath -F
multipath -v2

<td width="460">
  <span class="fontstyle0">顯示從 </span><span class="fontstyle2">sysfs </span><span class="fontstyle0">與 </span><span class="fontstyle3">device mapper </span><span class="fontstyle0">蒐集而來的 </span><span class="fontstyle3">multipath </span><span class="fontstyle0">設定。</span>
</td>

<td width="460">
  <span class="fontstyle0">顯示從 </span><span class="fontstyle2">sysfs</span><span class="fontstyle0">、</span><span class="fontstyle3">device mapper</span><span class="fontstyle0">、與其它系統的可用元件蒐集而來的<br /> </span><span class="fontstyle3">multipath </span><span class="fontstyle0">設定。</span>
</td>

<td width="460">
  <span class="fontstyle0">移除指定的 </span><span class="fontstyle3">multipath </span><span class="fontstyle0">裝置。</span>
</td>

<td width="460">
  <span class="fontstyle0">移除所有未使用的 </span><span class="fontstyle3">multipath </span><span class="fontstyle0">裝置。</span>
</td>

<td width="460">
  <span class="fontstyle0">（</span><span class="fontstyle3">Red Hat Enterprise Linux 6.6 </span><span class="fontstyle0">以上）移除</span><span class="fontstyle2">wwids </span><span class="fontstyle0">檔案中特定裝置的<br /> </span><span class="fontstyle2">wwid</span><span class="fontstyle0">。</span>
</td>

<td width="460">
  <span class="fontstyle0">（</span><span class="fontstyle3">Red Hat Enterprise Linux 6.6 </span><span class="fontstyle0">以上）重新設定</span><span class="fontstyle2">wwids </span><span class="fontstyle0">檔案，以僅納入現有<br /> 的 </span><span class="fontstyle3">multipath </span><span class="fontstyle0">裝置。</span>
</td>

選項描述

-l

-ll

-f 裝置

-F

-w device

-W

5.10. 使用 DMSETUP 指令，決定 DEVICE MA

其他細節

https://access.redhat.com/documentation/zh-tw/red_hat_enterprise_linux/6/pdf/dm_multipath/Red_Hat_Enterprise_Linux-6-DM_Multipath-zh-TW.pdf