Udev rules does not work

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux(RHEL) 6
  • Red Hat Enterprise Linux(RHEL) 7

Issue

  • Udev rules for creating asm disk symlinks to multipath devices does not work

Resolution

Example content of udev-rules file

ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940A802D001671617E1196E123",NAME+="oracleasm/disk01",OWNER="oracle",GROUP="oinstall",MODE="0660"
ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940A802D00F44429CD1196E123",NAME+="oracleasm/disk02",OWNER="oracle",GROUP="oinstall",MODE="0660"
ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940A802D003689B9D91196E123",NAME+="oracleasm/disk03",OWNER="oracle",GROUP="oinstall",MODE="0660"

Udev rule's matching algorithm is case sensitive, the ENV{DM_UUID} field value does not match the real value. This is because the value within the rule has uppercase letters (for example, ...940A... ) while the actual field value has lower case letters (for example, ...940a... ).

Use the UUID output from #udevadm info --query=all --name=/dev/mapper/
Do not use UUID output from multipath -ll command

Correct example content of udev-rules file

ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940a802d001671617e1196e123",NAME+="oracleasm/disk01",OWNER="oracle",GROUP="oinstall",MODE="0660"
ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940a802d00f44429cd1196e123",NAME+="oracleasm/disk02",OWNER="oracle",GROUP="oinstall",MODE="0660"
ACTION=="add|change",ENV{DM_UUID}=="mpath-8937058940a802d003689b9d91196e123",NAME+="oracleasm/disk03",OWNER="oracle",GROUP="oinstall",MODE="0660"

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