Le 13/12/2024 à 09:04, Patrik Schindler a écrit :
Hello Diego,
Am 12.12.2024 um 23:22 schrieb Diego E. KESSELMAN <diegokesselman@xxxxxxxxx>:
Maybe IBM should have some kind of NFS procedure based on BRMS or just a command, to take your Remote Image Catalog and BOOTP image in one step to a mounted NFS directory. This could lead to a poor man's VTL using a Linux Server.
Why would one need to fiddle with bootp if there's a VTL he can (hopefully!) already boot from?
Let me talk about what was my use case. It was before my retirement, 3
or 4 years ago (many new techniques are available now, such as VTL or
Migrate While Active
https://www.ibm.com/support/pages/ibm-i-migrate-while-active which were
not at this time), and I had to deal with a request from management
about how to migrate a full IBM i partition to IBM PowerVS (IBM i
cloud), possibly with as less downtime as possible (for example a full
backup in restricted state requires too much time). Basically, for a
POC, we used a similar technique as described in Migrate While Active,
except that data synchronization was provided by some replication
software (I don't remember exactly but possibly based on Mimix/QuickkEDD
products provided by Precisely).
So we used a local optical image catalog to run a SAVSYS, and save QGPL
and QUSRSYS which were required to scratch install an IBM i partition
able to be used by Precisely to set up and start their replication
product. This image catalog was then used on a temporary IBM i partition
installed in PowerVS and dedicated to provide remote image catalog, so
able to run the VFYIMGCLG command it order to create BOOTP directory and
required files. On the target IBM i partition (fully loaded and usable
when created by PowerVS, but containing none of the source partition
objects), we could simulate a *manual* upgrade over the remote image
catalog, with PWRDWNSYS IPLSRC(*IMGCLG) IMGCLG(remote_catalog) because
we don't have access to the HMC, similar to a D-Manual IPL, in order to
be able to select the appropriate option in the first menu to clear all
the disks when restoring microcode, then restore IBM i, then restore
QGPL and QUSRSYS. So far, so good.
Note : the content of the image catalog was not heavy (let's say around
1 TB), so transferring it through the network was not really an issue.
But, there was a huge cost gap on PowerVS between an IBM i partition and
a Linux one. So another POC was to try to use, in place the temporary
IBM i partition, a temporary Linux partition to provide bootp and nfs
services for a remote image catalog. Too late for me for trying it, it
was retirement time :-)
Of course, this way to proceed was not designed for on-going activities,
but only for one-time migrations.
:wq! PoC
midrange.com
