Arnulfo:
First, note that your client should be migrating to v14.10 not v12.10. That is because v15.0 has been released and within the year IBM will likely announce end-of-support for v12.10 to take effect in 2026 or 2027.
On to your question. If the client is already using ER, then you just have to set up the new servers on Linux, then using the oncsm on the new server (not the v11.70 version) add the new servers and replicate the tables to the new server. The replication should be bidirectional so that if they discover any problems when they move their applications over they can easily fail back to using the original AIX cluster until they work out a resolution. Once the new servers have synced with the existing cluster, then the client can move their applications to point to the new servers.
Another good reason to migrate to v14.10 instead of to v12.10 is the migrate database option in v14.10 which will automatically create replicants for every table in a single command.
Art
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Art S. Kagel, President and Principal Consultant
ASK Database Management Corp.
www.askdbmgt.com------------------------------