Admin Alert: Six Techniques to Prevent Power i Upgrades from Slowing Down
February 16, 2011 Joe Hertvik
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When I’m ready to perform a significant software or hardware upgrade, I use a series of techniques to cut upgrade time, avoid mistakes, and avoid delays. This week, I’ll review six of those techniques in the hope that you can use some of them to make your next Power i upgrade go easier. Keeping the Upgrade from Slowing Down I’ve always found that you can never increase Power i upgrade speed, you can only stop an upgrade from slowing down. In no particular order, these six tips can help you reduce the amount of waiting time in the Power i upgrade process; eliminate unnecessary time spent in restarting the system; and avoid wasted time by preventing easily identifiable mistakes.
Here’s how each of these tips can reduce unnecessary time during the upgrade process. Technique #1: IPLing Into Restricted State Benefit: Saves time when you need to put your system in restricted state after an IPL. System upgrades may require you to IPL your system to a quiet partition in restricted state. You can easily set up your system to IPL into restricted state by performing the following steps. 1. Using a user profile that has security administrator (*SECADM) and all object authority (*ALLOBJ) authorities, enter the following Change IPL Attributes (CHGIPLA) command and press F4 to prompt the command. CHGIPLA You’ll see a screen that looks like this.
2. Change the Start To Restricted State parameter on the Change IPL Parameters screen to *YES and press ENTER. When set to *YES, Start To Restricted State tells i/OS to start the system in restricted state the next time you IPL. Use this value if you need to IPL the system without starting your controlling subsystem. Please note that after your system IPLs into restricted state, the operating system will reset the Start To Restricted State parameter back to *NO. So if you need to IPL into restricted state more than once, you’ll need to reset the Start To Restricted State parameter to *YES every time you want the system to come up in restricted state. Technique #2: Stopping Your System from Restarting After a Full System Backup Benefit: Saves time after a full system backup by preventing the startup program from running. When performing a system upgrade or a hardware upgrade, you may need to take a full system backup without restarting your system after the backup completes. This is a problem in i/OS because while you can IPL an iSeries, System i, or Power i partition into restricted state, you can’t put your system into restricted state after a full system backup (GO SAVE, option 21). To understand how this works, here is the sequence of events that i/OS uses to restart your system startup program after a full system backup completes. 1. The system restarts the subsystem specified in the Controlling Subsystem System (QCTLSBSD) value. This value is set to the QSYS/QCTL subsystem by default. You can run the following Display System Value (DSPSYSVAL) command to determine which subsystem is your controlling subsystem. DSPSYSVAL SYSVAL(QCTLSBSD) 2. If QCTL is your controlling subsystem (or you’re using another subsystem based on QCTL’s parameters), upon activation the subsystem starts an autostart job called QSTRUPJD. This job is designated in QCTL’s Autostart job entries and it is started by using the parameters in the QSYS/QSTRUPJD job description. If you want to double-check the Autostart job entries for your system, display your subsystem description by running the following Display Subsystem Description (DSPSBSD) command. DSPSBSD SBSD(subsystem library/subsystem name) You’ll see a screen similar to this one.
Take option 3, Autostart job entries, and you’ll see this screen, which tells you that the subsystem will autostart the job listed in the QSYS/QSTRUPJD job description.
3. The QSTRUPJD job description specifies in its request data parameter that it will call the QWDAJPGM system program. QWDAJPGM checks the value in the Startup Program System (QSTRUPPGM) value and it then calls that program to start the system. This is why after an IPL or a full system backup, you’ll see the QSTRUPJD program running when the system starts. Given this subsystem setup, it’s easy to short-circuit the process and insure that your system startup program doesn’t run after you IPL or after you perform a full system backup. All you have to do is change the name of your system startup program in QSTRUPPGM to the *NONE literal. To do this, run the following Change System Value (CHGSYSVAL) command. CHGSYSVAL SYSVAL(QSTRUPPGM) VALUE(*NONE) After this change, the startup program will not run no matter how many times you IPL or back up your system. This comes in handy for long weekend upgrades that may consist of a number of IPLs, system restores, and a full system backup or two. As long as QSTRUPPGM is set to *NONE, your i/OS partition will start your controlling subsystem but your system startup program will never run. When you’re finished with your work, change QSTRUPPGM back to your normal system startup program value (you did remember to write down that program name and library, didn’t you?) and your system will start up again after an IPL or system backup. Technique #3: Giving Your System More Power Benefit: Decreases installation time by providing more CPU processing power and memory. If you’re performing a software upgrade that will take a long time to complete and needs more horsepower, consider stealing CPU and memory from other system partitions if that’s an option. Let’s say you’re upgrading the software on your production partition and you also run a development partition that uses 1 CPU and 8 Gb memory on the same machine. Make a rational decision as to whether your secondary partitions can get away with using less CPU and memory and if that works for your organization, temporarily move that memory to the partition being upgraded. Depending on the upgrade, this could help you complete your work faster. For an example of how to move system memory, see this article on moving system memory between partitions. Technique #4: Setting the QSYSOPR Message Queue to *BREAK Benefit: Decreases disk changing speed when loading software or PTFs. When you’re loading software or PTFs from multiple discs, the load program will usually send an inquiry message to the QSYSOPR message queue when it wants you to load up the next disc. However, that message will not show up on your system console or 5250 screen while you’re loading the software. To view and answer these QSYSOPR load messages, you have to take a System Request→6 to tell i/OS that you’ve loaded the next disc into your media reader. To make inquiry messages automatically pop up on your 5250 screen so that you can answer the message without having to go into the System Request menu, type in the following Change Message Queue (CHGMSGQ) command. CHGMSGQ MSGQ(QSYSOPR) DLVRY(*BREAK) This puts the QSYSOPR message into break mode on your screen. You can then start loading software or PTFs from your 5250 screen. When it’s time to load the next disc on your system, the operating system inquiry message will automatically pop up on your screen so that you can answer the message immediately without entering System Request→6. Technique #5: Labeling Cords and Cables Before You Begin Benefit: Avoids extra time in determining cable connections and may help you avoid cabling errors. If you’re performing any kind of hardware upgrade, be sure to label all the cords and cables going to your existing box before you remove or add any hardware. Label the cables themselves as well as their matching outlets or ports that they should plugged back into. Be sure to also label the cable with any special identification that may be needed for new equipment, such as which network the cable is connected to. Once you start untangling cables from your cable arms to put in new equipment, you’ll be glad you know exactly which cable or power cord goes where. Technique #6: Make Sure Additional Cables, Network Connections, and Power Outlets are Ready Benefits: Saves time by pre-identifying and installing all necessary cables, connections, and additional power requirements. Again, if you’re installing new hardware, make sure that you have all the necessary cables, network connections, additional power outlets, and new power cables that you need. Make sure that your cables are the right lengths so that they are long enough to reach from one end of the connection to another. You don’t want to wind installing your new hardware only to find that you’re short a cable or you don’t have enough electrical outlets. RELATED STORY Why Can’t I Move System Memory Between Partitions
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