tag:blogger.com,1999:blog-8750297140750368021.post4160788115013537782..comments2023-11-13T02:59:09.581+00:00Comments on Mainframe Update: Disaster recoveryTrevor Eddollshttp://www.blogger.com/profile/01503760088127669481noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-8750297140750368021.post-45601017994803333652008-03-19T23:23:00.000+00:002008-03-19T23:23:00.000+00:00Trevor,I’ve implemented a few GDPS/XRC networks an...Trevor,<BR/><BR/>I’ve implemented a few GDPS/XRC networks and I thought I might comment on the couple of issues you raised in your last paragraph. <BR/><BR/>First of all, regarding “problems with certain types of disks”, I cannot say that my experiences have pointed to anything in particular that would either confirm or deny this statement. However, I can think of a few factors that might contribute to this impression.<BR/><BR/>The overall health of the mirroring environment (and this is true for the various flavors of PPRC as well as XRC) is so closely tied to the microcode that any anomaly can quickly compound the error. This in turn can cause the mirroring environment to suspend (temporarily halt mirroring) in order to preserve the data consistency of the target volumes and protect the performance of the production environment. <BR/><BR/>Another consideration is that since the code is licensed by IBM, there could be some delay in implementing new functionality by other vendors.<BR/><BR/>“Channel problems” on the other hand is an area where certain configuration choices can definitely cause unexpected results. When you introduce a network component into the stable channel environment we have all come to know and love, it can often result in unnecessary weirdness.<BR/><BR/>Simply stated, when your channels run across a network – with or without additional channel extension equipment – many of the usual axioms we have depended upon to understand and configure the environment no longer apply. In fact, it is critical to understand how each component in the extended channel environment operates both individually and as a part of the greater whole. <BR/><BR/>The good news is that configuration issues as well as microcode bugs get fixed. And utilizing GDPS is indeed a “user friendly” environment!<BR/><BR/>Regards,<BR/><BR/><A HREF="http://recoveryspecialties.com" REL="nofollow">Mike Smith, Recovery Specialties</A><BR/><A HREF="http://enterprisestoragesolutions.blogspot.com" REL="nofollow">Enterprise Storage Solutions Blog"</A>Mike Smithhttps://www.blogger.com/profile/12776974972669620369noreply@blogger.com