IPLs and system maintenance was Re: PDSE
On 21 Jan 2012 08:07:01 -0800, in bit.listserv.ibm-main you wrote: On 01/21/2012 07:54 AM, Peter Relson wrote: how does IBM suggest doing a compress on a Linklist lib that needs compressing, inquiring minds would love to know There is no suggestion. This is simply not an operation that is supported or can be supported in general. Peter Relson z/OS Core Technology Design So the only functionally-equivalent, officially-sanctioned way to accomplish this goal is still to (1) create a new dataset with a different name and copy the data to it, (2) modify PARMLIB LNKLST defs to replace the old library in linklist with the new at next IPL, (3) IPL. And if for some reason you really must have the original dataset name, repeat the process to get back to the old name. All the other techniques that have been described here in the past to achieve this and bypass or defer the need for an IPL either don't guarantee the new library will be seen by all address spaces or carry some risk. While those of us who have been around long enough are fairly certain of specific cases at our own installation where the risks of alternative methods are small enough and acceptable, it is understandable that IBM does not wish to endorse techniques whose success depends on SysProg competence and judgement and also in many cases upon the tacit cooperation of Murphy in keeping unrelated system failures from occurring in a narrow transition window during which libraries and PARMLIB might be in a state where successful IPL and recovery from system failure is not be possible (without an independent z/OS recovery system). This discussion reminds me of when I was in a shop that had both Tandem and an IBM mainframe. The notice for a systems maintenance upgrade on the Tandem was that the operator would institute a simple procedure at a specific time with no outage. I think at one time IBM owned a computer company (Sequent?) that claimed to be able to do the same thing. I know that I was impressed by the Tandem capability. Clark Morris -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: IPLs and system maintenance was Re: PDSE
IBM once owned the Stratus line, a competitor to Tandem, and called it the System/88. http://en.wikipedia.org/wiki/Stratus_Technologies On Sat, 2012-01-21 at 14:19 -0400, Clark Morris wrote: On 21 Jan 2012 08:07:01 -0800, in bit.listserv.ibm-main you wrote: On 01/21/2012 07:54 AM, Peter Relson wrote: how does IBM suggest doing a compress on a Linklist lib that needs compressing, inquiring minds would love to know There is no suggestion. This is simply not an operation that is supported or can be supported in general. Peter Relson z/OS Core Technology Design So the only functionally-equivalent, officially-sanctioned way to accomplish this goal is still to (1) create a new dataset with a different name and copy the data to it, (2) modify PARMLIB LNKLST defs to replace the old library in linklist with the new at next IPL, (3) IPL. And if for some reason you really must have the original dataset name, repeat the process to get back to the old name. All the other techniques that have been described here in the past to achieve this and bypass or defer the need for an IPL either don't guarantee the new library will be seen by all address spaces or carry some risk. While those of us who have been around long enough are fairly certain of specific cases at our own installation where the risks of alternative methods are small enough and acceptable, it is understandable that IBM does not wish to endorse techniques whose success depends on SysProg competence and judgement and also in many cases upon the tacit cooperation of Murphy in keeping unrelated system failures from occurring in a narrow transition window during which libraries and PARMLIB might be in a state where successful IPL and recovery from system failure is not be possible (without an independent z/OS recovery system). This discussion reminds me of when I was in a shop that had both Tandem and an IBM mainframe. The notice for a systems maintenance upgrade on the Tandem was that the operator would institute a simple procedure at a specific time with no outage. I think at one time IBM owned a computer company (Sequent?) that claimed to be able to do the same thing. I know that I was impressed by the Tandem capability. Clark Morris -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- John McKown Maranatha! -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: IPLs and system maintenance was Re: PDSE
joa...@swbell.net (John McKown) writes: IBM once owned the Stratus line, a competitor to Tandem, and called it the System/88. http://en.wikipedia.org/wiki/Stratus_Technologies minor nit *not owned* ... provided enormous amount of money to rebrand sell as system/88. there is some folklore regarding just how many system/88s were actually installed ... about how some marketing teams would go in after IBM was bringing along a prospect and offer them an un-rebranded flavor at lower price. i marketed ha/cmp against both system/88 and stratus in much of the system/88 period ... past posts mentioning ha/cmp http://www.garlic.com/~lynn/subtopic.html#hacmp part of the marketing at the time was that stratus (and system/88) was purely fault-tolerant hardware .. but required scheduled system downtime and reboot for many times of software maintanance. For some customers with 5-nines availability requirement ... a century of outage budget could be blown with each annual maintenance scheduled outage. ha/cmp didn't have equivalent individual system uptime ... but lots of environments, clustered operation masked any single system outage ... providing overall cluster availability much better than 5-nines. Individual scheduled system maintenance could be done with rolling outage of individual cluster members. Stratus responded they could configure for cluster operation ... but that negated the need (and expense) for real fault tolerant hardware (in all those scenarios that I was able to demonstrate clustered fault masking recovery). Somewhat as a result, I got asked to do a section in the corporate continuous availability strategy document ... but after both Rochester (as/400) and POK (mainframe) whined that they couldn't meet the objectives, my section was pulled. -- virtualization experience starting Jan1968, online at home since Mar1970 -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
