Radoslaw Skorupka wrote: >Not so long time ago, when z800 was current machine *every* eth link >down event required CHPID OFF/ON for the affected OSA card. >So, assuming your system is communicating with rest of the wolrd (using >OSA card) it was comparable to POR or IML, because *all* LPARs lost >communication.
No, it was not comparable to a machine POR or IML and no, all LPARs did not lose communication...with the assumption that you weren't doing something "silly" in your implementation. There was a CHPID off/on for the affected OSA adapter in the past. That wasn't a machine POR or IML, and it wasn't at all comparable to one. What has "always" been recommended best practice is that every critical LPAR (at least) always have (at least) complete dual physical pathing. That means (at least) two physical ports on two separate physical adapters, each connected to separate switches... all the way through to separate network carriers, separate cable trenches, separate power infrastructure support, etc., etc. And thus if one link is interrupted for whatever reason (including a whole adapter reset/restart, or repair event, or whatever), the LPAR(s) still has(have) network connectivity through the other completely separate path(s). That's still recommended best practice, at least for critical operations, even as z System platform capabilities continue to improve (e.g. elimination of CHPID off/on). In the event Samat's employer has not adopted recommended best practice(s) then it's still not too late to avoid outages. Do the "adds" first, *then* (after careful verification) "subtract." -------------------------------------------------------------------------------------------------------- Timothy Sipples IT Architect Executive, Industry Solutions, IBM z Systems, AP/GCG/MEA -------------------------------------------------------------------------------------------------------- E-Mail: [email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
