io_setup failed errors when using multipath commands

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Environment

SUSE Linux Enterprise Server 12 Service Pack 1 (SLES 12 SP1)
SUSE Linux Enterprise Server 12 Service Pack 2 (SLES 12 SP2)

Situation

multipath commands cause io_setup failed messages. The following error messages have been observed in the output after running multipath -ll and multipath -v3:

io_setup failed

Resolution

Increasing (tripling) the value of aio-max-nr resolves the errors.

These changes can be performed by adding or modifying the following in /etc/sysctl.conf

fs.aio-max-nr = 1048576

or adding an entry to a local sysctl file, for example, appending the following to /etc/sysctl.d/99-sysctl.conf:

fs.aio-max-nr = 1048576

Cause

aio-max-nr value was set too low

Additional Information

Disclaimer

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