On Mon, Apr 5, 2010 at 1:38 PM, Steve Traylen <[log in to unmask]> wrote:
> On Mon, Apr 5, 2010 at 2:46 AM, John Bland <[log in to unmask]> wrote:
>> Hi,
>>
>> Liverpool have failed a number of SAM tests over the last day or so,
>> which seem to have all resulted from missing entries in BDII or being
>> unable to connect to lcg-bdii.gridpp.ac.uk.
>>
>> Other sites have had a number of failed tests over the same period.
>> We've also seen a number of temporary blips in our SAM tests over the
>> past few weeks, resulting from a lack of entries for our SE in BDII.
>> We've been unsure if this is anything to do with our glite 3.2 BDII or a
>> flaky VM system.
>>
>> As some of the recent tests have included lack of entries for external
>> systems as well I'm wondering if the GridPP BDII server is experiencing
>> problems for other sites as well and if other Tier2 sites without
>> problems are using a different top BDII.
>>
>> Should we all be using the same BDII or is there something to be gained
>> from a *coordinated* distribution of external services to mitigate the
>> otherwise single point of failure that BDIIs can represent within the UK
>> cloud?
>
> There are couple of things to look at here:
>
> You can use an A record in the DNS which has ip address at multiple
> institutions. Some of the regions do this. The ldap libraries will
> fail over nicely if they get a tcp reject, e.g because a site is
> completely down.
>
To confirm it is central europe who does this.
$ host bdii.ce-egee.org
bdii.ce-egee.org has address 161.53.0.235
bdii.ce-egee.org has address 195.113.219.26
$ host 161.53.0.235
235.0.53.161.in-addr.arpa domain name pointer bdii-egee.srce.hr.
$ host 195.113.219.26
26.219.113.195.in-addr.arpa domain name pointer bdii1.egee.cesnet.cz.
i.e one in Serbia and one in the C-Republic.
Steve.
> Sites can also use a
> LCG_GFAL_INFOSYS=bdii1.example.org,bdii2.example2.org
>
> Though only in some cases. WNs and UIs should be okay in particular but
> WMS can not use this.
>
> Steve.
>
>
>
>
>>
>> John
>>
>> --
>> Dr John Bland, M.Phys.(Hons), Ph.D. (Liverpool)
>> Email: [log in to unmask]
>> Phone: 0151 256 7055, Mobile: 07794 935 213
>> Web : http://www.third-bird.co.uk/photography/
>> "Happy Happy Joy Joy Joy!" - Stimpy
>>
>
>
>
> --
> Steve Traylen
>
--
Steve Traylen
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