Must all cluster nodes be offline when upgrading an indexer cluster from Splunk 6.3 to 6.4?

[jeff]

The upgrade instructions for indexer clusters specifies:

When you upgrade from a 6.x, such as 6.2, indexer cluster to a 6.3 cluster, you must take all cluster nodes offline. You cannot perform a rolling, online upgrade.

What about upgrading a 6.3 cluster to 6.4? I presume it's "safe" to follow this advice, but the phrasing sorta implies a rolling upgrade is possible...

[Steve_G_ · Accepted solution]

Good point. I will immediately update that material. The information is valid when doing any 6.x upgrade.