io_setup failed errors when using multipath or LVM commands

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Environment

SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP4
SUSE Linux Enterprise Server 12 SP3
SUSE Linux Enterprise Server 12 SP2
SUSE Linux Enterprise Server 12 SP1

Situation

multipath or LVM commands outputs `io_setup failed' messages. The following error messages have been observed in the output after running `multipath -ll', `multipath -v3' or LVM commands:

# lvs
io_setup failed
Failed to create bcache io engine.

# pvs
io_setup failed
Failed to create bcache io engine.

# vgs
io_setup failed
Failed to create bcache io engine.

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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