user9506868 wrote:You can have separate tops and the shared apps tier is not configured by default (or a standard approach). However, in R12 a unified APPL_TOP was introduced, which means you will find the same files on every application tier node -- https://forums.oracle.com/forums/search.jspa?threadID=&q=Unified+AND+APPL_TOP&objID=c3&dateRange=all&userID=&numResults=15&rankBy=10001
I am testing upgrading from 188.8.131.52 to 12.1.3. We currently have 3 Apps tier servers. I understand in R12, shared apps tier is standard. Is this true? Is this required or can we have separate tops on each node like in 184.108.40.206?
Does it mean I lay down the software on all three nodes and configure on all three nodes, during the upgrade?No, you lay down the R12 software on one node and do the upgrade then you add the other nodes.
Does it mean that I have 3 physcial servers with NFS mount to a shared SAN storage where the APPL_TOP, COMMON_TOP, AS 10.1.2 and AS 10.1.3 reside? And each of the three nodes will have its own INST_TOP?Correct.
Should the INST_TOP be on separate storage on each node, such as local storage?Yes -- This is also mentioned in [ID 384248.1], under "Instance Home" section.
Does it mean that when I install apps patch on the nodes, I basically invoke adpatch from any of the nodes and patch all the tops in one shot?I have answered this question above.
How about autoconfig? Do I run it once from any node? Will it update the config files on all nodes? Or do I run it on each node since each node has separate INST_TOP?On each node once you finish the upgrade and add the other apps tier nodes.