Hi,

I am trying to use FLM and see how it could be usefull.

So I setup a little demo consisting of a DMX-4, a VMAX-2 and an AIX Host (using PowerPath).

4 LUNs are used in the FLM session and the 4 are used on the AIX host to build a single JFS2 FS.

On the host, too, I created a little script to simulate an application activity which  basically write and delete data from the LUNs I try to migrate:

while (1) {
  for $i (1 .. 50) {
    sleep(2);
    print "Writing /flm_jfs2/random_".$i.".tmp\n";
    `dd if=/dev/urandom of=/flm_jfs2/random_$i.tmp count=6000 bs=1024`;
  }
  for $i (1 .. 50) {
    `rm -f /flm_jfs2/random_$i.tmp`;
  }
}

I create, activated the FLM session while the script was running and here is the ouput:

Writing /flm_jfs2/random_14.tmp

6000+0 records in.
6000+0 records out.
Writing /flm_jfs2/random_15.tmp

dd: 0511-053 The write failed.: Invalid file system control data detected.
dd: /flm_jfs2/random_15.tmp: Invalid file system control data detected.
dd: /flm_jfs2/random_15.tmp: Invalid file system control data detected.
Writing /flm_jfs2/random_16.tmp

6000+0 records in.
6000+0 records out.

Looking at what I have in the /flm_jfs2/ directory, it confirmed the error:

# ls -l /flm_jfs2/random_15.tmp
-rw-r--r--    1 root     system       159744 Jun 16 10:58 /flm_jfs2/random_15.tmp
# ls -l /flm_jfs2/random_14.tmp
-rw-r--r--    1 root     system      6144000 Jun 16 10:58 /flm_jfs2/random_14.tmp

So, since an error occured during the migrate process, and that my file was not able to be written on my FS, why would I use FLM?

It is supposed to be a non-interruption migration process, while we see that the application is impacted.

So, is my use case dumb? or did I miss something in my configuration?

Thank you for helping my understanding the value of FLM I missed during this demo.

Regards