The software described in this documentation is either in Extended Support or Sustaining Support. See https://www.oracle.com/us/support/library/enterprise-linux-support-policies-069172.pdf for more information.
Oracle recommends that you upgrade the software described by this documentation as soon as possible.

2.2.41 Boot from SAN installation fails using multipath on Pure Storage FlashArray

Systems installed with Oracle Linux 6 update 9 and configured to use the UEK R4 kernel fail to boot if the boot disk is a multipath LUN on a Pure Storage FlashArray. The system boots successfully if the LUN is exposed on a single path, or if the system is installed using Oracle Linux 6 update 8. The system is also able to boot successfully if configured to use the RHCK.

The exact cause of the issue is currently under investigation, but was replicated using a Pure Storage FlashArray FA-420 Pure Array and a QLogic QLE2562 HBA. (Bug IDs 26732037, 27093062).