On Thu, 23 Apr 2009, Maarten Litmaath wrote:
> Hi Valery,
>
>> we are investigating the possibility to move our old SE hosts
>> and GlueServiceUniqueIDs to the new scheme with all different
>> host names. For the quite internal reasones we forced to do
>> so in next few days, in really at the end of the month, so it
>> vary urgent to us.
>> Our old SE dCache is a bit old in s/w and h/w and full
>> of users data about 47TiB from 80 in total space on the board.
>> Currently we've installed the new instance of dCache on the
>> 2 new servers and 16 pools. We've tested that we can upgrade
>> an old pool and join it to the new instance, but we are not
>> absolutely sure about name space in dCache.
>> So, our plan #1.
>> 1.1 - fill a down time for 2 days in GOCDB;
>> 1.2 - stop the old SE;
>> 1.3 - join old pools to the new dCache;
>> 1.4 - move name space and DBes to the new dCache servers;
>> 1.5 - add new dCache as SE-SRM to th GOCDB;
>> 1.6 - move the name of the old SE in DNS to the new SE as
>> host alias;
>> 1.7 - start w/ new SE only and hope for the best.
>> The tricki parts are: 1.4 and 1.6 because we don't known
>> how it would work in reality and what would be the side
>> effect of host alias w/o host cert for the real hostname with
>> proper host cert.
>
> You can open a GGUS ticket for dCache Support and ask advice.
>
>> So, we have a plan #2.
>> 2.1 - run with 2 SE for some time, probably for < 1 month;
>> 2.2 - ask all supported VOs to move data to the new SE;
>> 2.2a - or move the data by ourself and ask VOs to change
>> SE to the new name in LFC;
>> 2.3 - stop old SE and decommission it finally.
>> The main question is, how it would be difficult to VOs to
>> move his data or change SE name in his central LFC/interlan DB?
>>
>> Does anybody in that list have experience in such reconfiguration,
>> or a similar job like moving VO's data from one SE to the another?
>
> Various sites have done similar operations: the site would move the data
> or rename the SE and then ask for the LFC to be updated by the LFC service
> managers (using an SQL script). This depends on the VO: not every VO
> uses an LFC. You should contact each VO you support e.g. via GGUS.
>
Thanks Maarten!
we just agreed internally to follow plan #2 with point 2.2
exactly as you suggest.
--
Best regards,
Valery Mitsyn
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