Hello George,
We briefly discussed yesterday about how to best reply to your request.
What you are asking for is currently not easy to achieve. Today, there is only this hack to try:
- Select few files you want to move from tape A to tape B and recall them into the repack instance. Here is example where they need to end up:
/usr/bin/xrdcp $recalled_file $EOS_MGM_URL/$EOS_REPACK_DIR/$VID/$fSeq_with_zeros
where at CERN:
EOS_MGM_URL="root://eosctarepack.cern.ch"
EOS_REPACK_DIR="/eos/ctarepack/production"
VID is the tape volume identified and for the fSeq_with_zeros try something like this:
for i in `/usr/bin/cta-admin --json tapefile ls -v $VID | /usr/bin/jq --raw-output ' .[] | .af.archiveId+" "+.tf.fSeq+" "+.af.size+" "+.af.checksum[0].type+" "+.af.checksum[0].value' | /usr/bin/awk '{if ($1 ~ /^
[0-9]+$/) print $2, $3, $4, $5}'`
do
# Extract the necessary information from the CTA tape file record
fSeq=$(echo $i | awk '{print $1}')
fSeq_with_zeros=$(echo $i | awk '{printf("%09d", $1)}')
- Once the files are in place on the REPACK instance - example:
pcvlado ~ > EOS_MGM_URL=root://eosctarepack eos ls -l /eos/ctarepack/production/I52620 | head -5
-rw------- 1 daemon daemon 6392670912 Sep 13 09:56 000000147
-rw------- 1 daemon daemon 4378111115 Sep 13 09:56 000000148
-rw------- 1 daemon daemon 8140800 Sep 13 09:54 000000187
-rw------- 1 daemon daemon 39931967 Sep 13 09:57 000000239
-rw------- 1 daemon daemon 5727365621 Sep 13 09:58 000000316
then you can try to run cta-admin repack add --vid VID --mountpolicy your_repack_mount_policy --no-recall.
The --no-recall option should ensure that there is no recall of any files from the source tape A and only the files which are in the buffer are migrated to the new destination tape B. You should see the number of the files you provided in the providedFiles column of the cta-admin repack ls command output.
Please note that what I just wrote above is a completely untested recipe. Please give it a try and report here how it went.
In the long run, we plan to provide a solution based on modifying the storage classes. The idea is that you would change storage class of some files (no production quality tool to do this exist today). Then according to the defined archive routes, those files would end up in a different tape pool.
Hope this helps. Best regards,
Vladimir