Re: Is it possible to prevent a structure into a particular CF (Coupling Facility)?



Hi Jan,
I'll try to answer your questions but I can't cover all aspects. Just give
some general ideas.
The CF Hint functionality is for duplexed structures and is designed to
ensure that the
instance at SITE2 is used in the case of a SITE1 disaster.
This functionality is available in GDPS/HM V3.3.

The question on where you place CF structures and whether they are duplexed
is very
dependent on your environment and business requirements. There are some
general
recommendations which would be true:
Have XCF signalling structures at both site1 and site2
Have ISGLOCK at site1 but have the KSYS LPAR weighted higher so that
ISGLOCK
it can be rebuilt at site2. (This area is complex and there are many
considerations)

The KSYS does have to be part of the production parallel sysplex and the
KSYS disk
must be at site 2 for a HyperSwap implementation.

If you are already doing CF duplexing at the production site you would not
necessarily
want to move the second copy to site2 for performance reasons. If you have
a single
site workload (all prod systems at site1) and there is a site1 failure you
will have to
IPL your systems at site 2 anyway and so duplexing across sites will not
buy much.

In fact, one way to implement GDPS/HM would be to have the KSYS LPAR at
site1 and
the KSYS disk at site2. All CF structures at site1 with the site2 CFs
defined in the CFRM
policy for use in the event of a site1 failure. This negates the need for
cross-site CF
and Timer links. The disadvantage is that KSYS would have to be IPL'd at
site2 first
before starting the recovery in the case of a site1 failure and adds about
20 minutes
to the RTO. There would be no difference for site1 disk failure. KSYS would
survive
as its disk is at site2 and perform the HyperSwap.

We can take further discussion off-list.

Regards,
George Kozakos

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to listserv@xxxxxxxxxxx with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
.



Relevant Pages

  • Re: Authentication
    ... Site1 and Site2 are two DCs of a single domain? ... PDC emulator FSMO of its domain as its time server. ... > NTP server which I assume would be the main time server ...
    (microsoft.public.windowsxp.security_admin)
  • RE: Nach DC-Entfernung falsche GUID im AD > keine Replikation
    ... Neuen Server mit NEUEM NAMEN per dcpromo integriert ... > Auf der Site1 habe ich DC2 nach Ausfall entfernen und neu aufsetzen müssen. ... > Konnte vorher noch alle FSMO's auf DC1 der Site1 seizen. ... > bevor der Metadata-Cleanup an die Site2 repliziert wurde. ...
    (microsoft.public.de.german.windows.server.active_directory)
  • One DC with three sites
    ... Site1, Site2, and Site3. ... For some reason the workstations and server in Site2 ... that replicates between the 3 sites and if we consolidated our site ...
    (microsoft.public.windows.server.active_directory)
  • Re: SMTP Connector
    ... how do the messages from Site1 know about the mail ... server handling the requests in Site2 without actually specifying the it ... specified the email domain of Site2, not the actual mail server. ...
    (microsoft.public.exchange.admin)