Spanning tapes or drives

YoYotta LTFS or Automation will span or split up large archives across multiple tapes.
In this example there are two LTO desktop drives and a main and safety copy is needed. So twice as many tapes will be needed.
However the same applies to creating a single spanned copy using one drive.
If spanning across tapes the job will be running for a while, so best to use direct attached fast source storage.
Turn off Quick Verify in Preferences as a full verify is needed when spanning tapes.
A spanned copy from a live volume (where files are being added/modified) is not supported. See the LTFS FAQ support page for more information.
If using an LTO library with YoYotta Automation the tapes for the job must ALL be loaded into library slots. So the maximum job size is limited to the library capacity. You will need to split up larger jobs. The tapes do not need to formatted manually.

Select first main and safety tapes

Load the tapes, if using a desktop drive format them in the LTFS panel. Click the + above the destination table. Select the tapes. Click Add COPY #1,2. In this example all our main tapes have odd serial numbers and safety tape numbers are even.

Ready to start

Now two jobs are ready. COPY #1 is the main and COPY #2 will be the safety copy.
There are 10 files to copy, the first three will fit onto each tape. Click the green button to start.

Backup space warning

YoYotta warns that the entire job will not fit on one tape. Click Continue.

More space needed

After the copy and verify, more space is needed, so YoYotta prompts to add new destinations.
If using desktop drives and the tapes are not already ejected, then select the first tape TP0001 and press the eject button in the top right. Repeat this for tape TP0002.

Append second Main tape

Important, don't delete the first tapes from the destination table, just eject them.
Once a spanned job has started it is important not to open Edit Paths or change any settings for the job.

Load new tapes, if using a desktop drive format them. Click the + above the destination table. Select tape TP0003 and click Append to COPY #1. This appends a new tape to the main copy.

Append second Safety tape

Click the + above the destination table. Select tape TP0004 and click Append to COPY #2. This appends a new tape to the safety copy.

Second tapes ready

Click the green arrow to start the job.
Before starting make sure that you see the Copied and Verified count for the previous tapes as shown here.

Second tapes complete

Now tapes are complete. There are some files left to copy. Eject the tapes and mount two more and start.

All finished

Now there is a green confirmation tick for COPY #1 and COPY #2. Eject the last two tapes.

YoYotta Automation

If you have an LTO tape library then you can load all the tapes at once and use YoYotta Automation to create an automated job.

Resuming a spanned job

If there is an issue during a spanned job, then the copied and verified file status for the job will be lost.
For example a power cut or if the source or destination drives are disconnected. Or if YoYotta or the Mac crashes.
Note that once a spanned job has started it is important not to open or try to adjust settings in the destination panel.
Also make sure that you do NOT have Quick Verify turned on in Preferences as spanning tapes requires full verification to be enabled.

If you have tried to resume the job then you may have seen the remaining size and file count jump back to the full job size.
This means that YoYotta has not been able to resume the job, instead starting again copying onto the last tape. In this case the last tapes for each copy will need to be reformatted.

To resume the job follow these steps.
Open the LTFS panel and mount the first tape for the copy. Add this to the destination table as COPY #1 if not already there.
If performing a parallel archive to two sets of tapes, then also mount the first tape from the second copy. Add this to COPY #2 if needed.
Make sure the destination paths are set exactly the same as the previous job.
Click the refresh button above the job table.
Make sure that you see the number of files copied and verified in the destination table.
If you don't see this then double check the destination paths to ensure they match the location of files on the tapes written so far.
Now load and mount the next tape for each COPY. If the tape is missing from the destination table append it to the COPY and then click refresh.
Again ensure you see the Copied and Verified count.
Repeat this for any further tapes and then click start.
YoYotta will check the tapes and resume copying.

© 2022 YoYotta Back to Top