How can I make sure that the device names, say /dev/xvda remains same across node reboots ? We have had Linux machines booting up with different /dev names in the past .
By using UDEV RULES, if you properly configure the UDEV RULES, it will perform its role properly.
On MoS, Oracle Docs and Oracle Blogs related matter shows many way to configure it.
I set ownership of LUNs via the udev multipath rules file as described in Re: Can I use udev rules file for 18.104.22.168 RAC on Oracle Enterprise Linux 6 ?
I use multipath configuration to configure the LUNs as described in Re: Install Oracle 11gr2 2Node RAC on ASM