R.S. writes: > As a z/OS user I manage I/O configuration using HCD. IOCDS is > created from IODF using text file (for the first time on new CPC) or > directly using internal communication to SE. > > Question: How can I manage I/O in Linux-only environment? > Do I have to code IOCP text file?
There are a few combinations depending on whether z/VM is available on the CEC, on site or not at all. z/VM provides two ways of managing I/O changes and both can either write a new IOCDS to an inactive slot (ready for a POR) or make Dynamic I/O changes to match up the live I/O configuration with an IOCDS slot. One is with HCD; the other is with the IOCP command and associated Dynamic I/O CP commands. HCD does mostly the same low-level stuff as on z/OS but doesn't have the ISPF panels so you either use the Windows-specific client-side app or your use z/OS on some other system (if available) to generate and export an IODF which z/VM HCD can import and use. Without HCD, you can write/maintain an IOCP text file, use the z/VM IOCP utility to write it to an IOCDS slot (ready for next POR) and then issue Dynamic I/O CP commands to change the current I/O configuration. Since Linux and z/VM don't care much about a lot of the O/S-level configuration stuff that z/OS puts in its IODF, an IOCP text file for a z/VM and Linux system tends to be not too complicated (e.g. under 100 lines of fairly simple statements). With HCD, it manages making those changes to keep things in sync between the newly-written IOCDS and the current configuration; without HCD, you need to be careful to issue the right commands to match your newly-written IOCDS or else at the next POR you will have a changed I/O config and resulting unhappiness. If you don't have z/VM (or z/OS) on the CEC at all then things get more restricted. You can certainly use the SE standalone IOCP task via HMC Single Object Operations to write an IOCP text file from a USB stick/ftp server into an IOCDS slot and do a POR - that gets you started, as always. Neither Linux nor KVM can make Dynamic I/O changes themselves so without z/VM your choices are either doing a POR whenever you want to make an I/O change (just pretend I'm keeping a straight face while saying that) or putting the whole CEC in Dynamic Partition Manager (DPM) mode. In that mode, you can only run Linux LPARs or KVM LPARs (for hosting Linux) - you can't run z/VM, let alone z/OS. In DPM mode, you get a pretty new HMC GUI for configuring LPARs which also supports making slick dynamic I/O changes but a CEC in DPM mode supports a more limited range of I/O (e.g. no ECKD, no Flash Express). --Malcolm -- Malcolm Beattie Linux and z Systems Technical Consultant, zChampion IBM UK Systems and Technology Group ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
