[lm-announce] Impending replacement of Zeus

[Jonathan Buzzard]

As you are all no doubt aware the performance of Zeus leaves a lot to be
desired. That is mainly because it was designed to cope with around
100GB of new data a week, and it now does well in excess of 100GB a day,
it is well beyond it's design limits and performs poorly as a result.

To address this we have a brand spanking new system. It has new larger
faster disks, new faster file servers, faster network connections, and
new more stable versions of the software with new features.

We are now in the final stages of getting the new system ready. The bulk
of the data, some 70TB has already been copied onto the new system.

However since that started there have been new files created and old
ones deleted on the existing system and further synchronization of two
systems is required.

The plan is as follows, during this week we will be running a preliminary
synchronization of the nine million files on the two systems. We
anticipate that this will take till the middle of the week. During this
period the performance of the existing system will be impacted. However
you can continue to use the system as normal during this period.

Then starting at 18:00 on the 30th January (Friday this week) the
existing system will be taken offline for a final synchronization.
Unfortunately it is not possible to maintain access to the system
during this final synchronization as we have to be sure that no
changes are made to the existing or new system while it takes place.

Once the final synchronization has completed the new system will be made
available to users. We currently anticipate the new system will be
available at the latest by the end of Monday the 2nd February.

During the next week however the actions of yourselves could have an
major impact on the time required for the final synchronization. During
this period I would implore users not to reorganize your their files. If
anyone does a reorganizing of their files this will significantly extend
the time required to synchronize the two systems. If you do decide to
ignore this and reorganize your files don't be surprised next Monday if
you find I have redirected a large number of angry users in your
direction when they have no access to their files.

Finally while we have done some extensive testing of the new system,
nothing substitutes for a hundred real end users. It is entirely
possible that further tuning of the new system will be required. Please
bear with us if this turns out to be the case.


JAB.




-- 
Jonathan A. Buzzard                      Tel: +441382-386998
Storage Administrator, College of Life Sciences
University of Dundee, DD1 5EH

The University of Dundee is a registered Scottish charity, No: SC015096