Re: Storage Management Enhancement Ideas
On Sunday, 09/20/2009 at 04:26 EDT, Rob van der Heij rvdh...@velocitysoftware.com wrote: On Sat, Sep 19, 2009 at 6:21 PM, John P. Baker jbaker...@comporium.net wrote: I recommend that the idea of splitting page space into multiple pools be considered, where individual users can be assigned to different pools. For the purposes of discussion, let us consider that following enhancement: I don't like the idea to use only a subset of your paging capacity for part of the workload. It's not just about space but also about throughput. This is imho a very complicated approach to exclude some (small) important users from an OOM killer. The real question is whether you can do an OOM killer at all and achieve something useful by doing so. Most performance tuning gets harder when you split resources and consumers in different groups and manage them separately. Sharing is easier with large numbers. And does not address the core issue: At some point, there is a shortage of resources. How should CP respond? o Deny the request? o Wait for the resources to be available? o Steal the resources from someone else? You can partition and reserve all the resource you want, but eventually you run out. Alan Altmark z/VM Development IBM Endicott
Re: Dropping VM 3270 Session
On Sun, Sep 20, 2009 at 12:00 PM, Moore, Terry A. t.mo...@timken.com wrote: I have a client in a small office in the UK that can not maintain a TN3270 session (Hummingbird Host Explorer) back to our VM host here in Ohio. It connect briefly and displays the logo screen then drop before he can enter a userid/password. If he goes to another of our UK offices, his PC connects perfectly. I was thinking network problem, yet he can connect to our OS/390 system fine and can even make the VTAM jump from there to the VM system for a CMS session with no problem. Any ideas on what we should be looking for? Could it be that the profile for the session specifies that you also want a printer session to be allocated and that it disconnects because VM does not support that? See if you can let the termulator trace the dialog and see why it disconnects. Rob
Re: Dropping VM 3270 Session
Rob, I'll look into the printer session settings. Thanks for the idea. I'm going to be surprised if that is it... but I've been surprised before. :-) Terry - This message and any attachments are intended for the individual or entity named above. If you are not the intended recipient, please do not forward, copy, print, use or disclose this communication to others; also please notify the sender by replying to this message, and then delete it from your system. The Timken Company / The Timken Corporation
Re: Storage Management Enhancement Ideas
Alan, I disagree. Yes, you still have the possibility of a resource shortage. However, partitioning provides the installation more flexibility in protecting critical resources. As far as how should CP respond, if sufficient page space is unavailable within a particular backing storage pool according to the criteria set forth, then the request (LOGON, DEFINE STORAGE) should be denied. John P. Baker -Original Message- From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Alan Altmark Sent: Monday, September 21, 2009 2:03 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Storage Management Enhancement Ideas And does not address the core issue: At some point, there is a shortage of resources. How should CP respond? o Deny the request? o Wait for the resources to be available? o Steal the resources from someone else? You can partition and reserve all the resource you want, but eventually you run out. Alan Altmark z/VM Development IBM Endicott
Re: Dropping VM 3270 Session
Turned out to be a wrong duplex setting on the switch in that remote office. Apparently VM was more susceptible to it than OS/390, but we expect that the OS/390 applications were running very slowly even though they weren't dropping. Terry From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Matthew Donald Sent: Sunday, September 20, 2009 9:49 PM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Dropping VM 3270 Session I'm guessing that there may be TCP/IP configuration differences between z/OS and z/VM. Do they use separate OSA's? Perhaps it could be a MTU issue - the classic 1500 vs 1492? On Sun, Sep 20, 2009 at 8:00 PM, Moore, Terry A. t.mo...@timken.com wrote: I have a client in a small office in the UK that can not maintain a TN3270 session (Hummingbird Host Explorer) back to our VM host here in Ohio. It connect briefly and displays the logo screen then drop before he can enter a userid/password. If he goes to another of our UK offices, his PC connects perfectly. I was thinking network problem, yet he can connect to our OS/390 system fine and can even make the VTAM jump from there to the VM system for a CMS session with no problem. Any ideas on what we should be looking for? Terry A. Moore IT Project Manager This message and any attachments are intended for the individual or entity named above. If you are not the intended recipient, please do not forward, copy, print, use or disclose this communication to others; also please notify the sender by replying to this message, and then delete it from your system. The Timken Company / The Timken Corporation - This message and any attachments are intended for the individual or entity named above. If you are not the intended recipient, please do not forward, copy, print, use or disclose this communication to others; also please notify the sender by replying to this message, and then delete it from your system. The Timken Company / The Timken Corporation
RACF DSMON Report
Hi How would I run a RACF DSMON report on z/VM? Thank You, Terry Martin Lockheed Martin - Information Technology z/OS z/VM Systems - Performance and Tuning Cell - 443 632-4191 Work - 410 786-0386 terry.mar...@cms.hhs.gov WFH on Tuesdays and Fridays
Re: RACF DSMON Report
If you can link to RACFVM 305, 490, and 200, you can run it in your own userid. Please issue IPL 490 before you start (an IPL CMS afterwards) 2009/9/21 Martin, Terry R. (CMS/CTR) (CTR) terry.mar...@cms.hhs.gov Hi How would I run a RACF DSMON report on z/VM? *Thank You,* *Terry Martin* *Lockheed Martin - Information Technology* *z/OS z/VM Systems - Performance and Tuning* *Cell - 443 632-4191* *Work - 410 786-0386* *terry.mar...@cms.hhs.gov* *WFH on Tuesdays and Fridays* -- Kris Buelens, IBM Belgium, VM customer support
Re: RACF DSMON Report
Kris, I did my links but when I tried to IPL 490 I received the following any ideas? 10:42:51 CP I 490 RACFVM CMS XA Rel 14 03/19/2002 6 *-* 'SYNONYM SYN' +++ RC(-3) +++ Ready; T=0.01/0.01 10:42:51 Thank You, Terry Martin Lockheed Martin - Information Technology z/OS z/VM Systems - Performance and Tuning Cell - 443 632-4191 Work - 410 786-0386 terry.mar...@cms.hhs.gov mailto:terry.mar...@cms.hhs.gov WFH Tuesdays and Fridays From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Kris Buelens Sent: Monday, September 21, 2009 10:24 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: RACF DSMON Report If you can link to RACFVM 305, 490, and 200, you can run it in your own userid. Please issue IPL 490 before you start (an IPL CMS afterwards) 2009/9/21 Martin, Terry R. (CMS/CTR) (CTR) terry.mar...@cms.hhs.gov Hi How would I run a RACF DSMON report on z/VM? Thank You, Terry Martin Lockheed Martin - Information Technology z/OS z/VM Systems - Performance and Tuning Cell - 443 632-4191 Work - 410 786-0386 terry.mar...@cms.hhs.gov WFH on Tuesdays and Fridays -- Kris Buelens, IBM Belgium, VM customer support
Re: Dropping VM 3270 Session
On Monday, 09/21/2009 at 09:29 EDT, Moore, Terry A. t.mo...@timken.com wrote: Turned out to be a wrong duplex setting on the switch in that remote office. Apparently VM was more susceptible to it than OS/390, but we expect that the OS/390 applications were running very slowly even though they weren't dropping. The only thing that happens when you incorrectly set half-duplex on a switch port is that many of the packets are dropped. (The port will not send and receive at the same time.) Those dropped packets will eventually result in retransmissions by the affected hosts. Best case is that throughput is cut in half. Depending on timing, the worst case is that the session drops. It would still be edifying to learn if it is VM or the emulator that is terminating the connection. Alan Altmark z/VM Development IBM Endicott
Re: Dropping VM 3270 Session
On Monday, 09/21/2009 at 04:10 EDT, Rob van der Heij rvdh...@gmail.com wrote: Could it be that the profile for the session specifies that you also want a printer session to be allocated and that it disconnects because VM does not support that? Now stop that. :-) z/VM has supported TN3720E printer sessions for many many many years. Alan Altmark z/VM Development IBM Endicott
Re: Storage Management Enhancement Ideas (was: VM lockup due to storage typo)
Bill, You may well be correct. Of course, that permits me to pose the question of how such a condition could effectively be avoided. Ideas, anyone? John P. Baker -Original Message- From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Bill Holder Sent: Monday, September 21, 2009 11:32 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Storage Management Enhancement Ideas (was: VM lockup due to storage typo) These are very interesting ideas, but I suspect (no way to prove, since no doc will be forthcoming) that the hang was not a paging issue, but rather a central storage fragmentation issue involving attempts to allocate four contiguous frames for region and segment tables. Don't let me throw cold water on the current discussion, though, I just wanted to point out that all of the interesting paging ideas probably wouldn't help the situation that triggered this entire discussion. - Bill Holder, z/VM Development, IBM
Re: RACF DSMON Report
The failing SYNONYM command doesn't matter: when you issue IPL 490, you run a modified CMS version: contains some extra stuff required for RACF, but misses quite some native CMS things. The SYNONYM command seems one of them. ( (this SYNONYM command is included in the PROFILE EXEC found on the 191 disk). 2009/9/21 Martin, Terry R. (CMS/CTR) (CTR) terry.mar...@cms.hhs.gov Kris, I did my links but when I tried to IPL 490 I received the following any ideas? 10:42:51 CP I 490 RACFVM CMS XA Rel 14 03/19/2002 6 *-* 'SYNONYM SYN' +++ RC(-3) +++ Ready; T=0.01/0.01 10:42:51 *Thank You,* *Terry Martin* *Lockheed Martin - Information Technology* *z/OS z/VM Systems - Performance and Tuning* *Cell - 443 632-4191* *Work - 410 786-0386* *terry.mar...@cms.hhs.gov* terry.mar...@cms.hhs.gov *WFH Tuesdays and Fridays* -- *From:* The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] *On Behalf Of *Kris Buelens *Sent:* Monday, September 21, 2009 10:24 AM *To:* IBMVM@LISTSERV.UARK.EDU *Subject:* Re: RACF DSMON Report If you can link to RACFVM 305, 490, and 200, you can run it in your own userid. Please issue IPL 490 before you start (an IPL CMS afterwards) 2009/9/21 Martin, Terry R. (CMS/CTR) (CTR) terry.mar...@cms.hhs.gov Hi How would I run a RACF DSMON report on z/VM? *Thank You,* *Terry Martin* *Lockheed Martin - Information Technology* *z/OS z/VM Systems - Performance and Tuning* *Cell - 443 632-4191* *Work - 410 786-0386* *terry.mar...@cms.hhs.gov* *WFH on Tuesdays and Fridays* -- Kris Buelens, IBM Belgium, VM customer support -- Kris Buelens, IBM Belgium, VM customer support
Re: VM lockup due to storage typo
I don't think the analogy to a ping attack is a particularly fair one. Yes, from the perspective of an innocent third user, they look the same, perhaps, but they aren't. If the attack were made through some sort of security gate that defaults to closed state which the sysadmin had accidentally opened and left open, I think that would be a more fair analogy. Quibbling over details, perhaps, but there is an important difference. On Fri, 18 Sep 2009 10:11:58 -0400, David Boyes dbo...@sinenomine.net w rote: On 9/18/09 9:32 AM, Bill Holder hold...@us.ibm.com wrote: That is indeed one important question, but there was another one, the question of whether this was a denial of service attack exposure, whic h i t is not. I think that's a point of view question. If I am another user on the same VM system, happy within my cozy little class G box, and the hypervisor admin does something outside of my contr ol to some OTHER user that causes CP to choke, then from the original user' s perspective it IS a DOS attack because it's something that is out of my control, starves ME, and causes ME to choke without reason. An analagous parallel case in the distributed system world would be a pi ng flood attack on a network segment. The innocent get hurt along with the intended target by being starved of access to the network, and thus lose the ability to function according to design. From the hypervisor admin's POV, then yeah, it's just doing what it's to ld to do. It's correct operation, working as documented. I think Bill Schuh and Marcy and myself are arguing for the former viewpoint. I think you and Adam are arguing from the latter view. I'm not disagreeing that it would be nice if there were some sor t of are you sure safety net before the system proceeded to try to do something suicidal, but that's a design and requirements question, not a defect question. I think we're all in violent agreement on that point. Now, the question is what is the best way to put a safety on that gun? = ===
Re: Dropping VM 3270 Session
On Monday, 09/21/2009 at 10:53 EDT, Alan Altmark wrote: It would still be edifying to learn if it is VM or the emulator that is terminating the connection. Unfortunately (for inquisitive souls such as Alan) our network team has already fixed the switch setting, so we shouldn't be getting the drops any more. If we do, getting a trace log from the emulator is the next step. Terry - This message and any attachments are intended for the individual or entity named above. If you are not the intended recipient, please do not forward, copy, print, use or disclose this communication to others; also please notify the sender by replying to this message, and then delete it from your system. The Timken Company / The Timken Corporation
z/VM Stopped Responding
Last week, while I was out of the office, we had our first unplanned z/VM outage. We are running z/VM 5.3 with about 20 guests. Symptoms were that a user tried to access a Linux guest to do a production code move around 10:00 PM. He was unable to get in. Then, the operators received lightening bolt messages and nothing on z/VM or any of the Linux systems were available. The ultimate resolution was to re-IPL. All was fine afterwards. My dilemma is that I'm not accustomed to debugging z/VM. I'd really like to look at the system logs for that time to see if there are any messages. I know that can be done, but for the life of me can not find any procedures to do it. Any help would be greatly appreciated. Thanks, Chuck Kreiter State Auto Insurance
Get unnamed printer file to my A disk from RDRL
Hi I have a printer file in my RDR and I want to receive it to my A disk but it is UN-NAMED how do I do this: (none) (none) PRT A M1P3 LPD1M911 NONE 334 9/21 14:25:33 Thank You, Terry Martin Lockheed Martin - Information Technology z/OS z/VM Systems - Performance and Tuning Cell - 443 632-4191 Work - 410 786-0386 terry.mar...@cms.hhs.gov WFH on Tuesdays and Fridays
Re: z/VM Stopped Responding
The real ultimate solution would have been to do a restart dump so that IBM could take a look at what was last happening on your system. Hopefully your OPERATOR id has its console output spooled to someplace. Type Q R OPERATOR or Q P OPERATOR. If you don't have VM:Spool, you need to get those spool file(s) 'owned' by your userid via the TRANSFER command. Then either PEEK the spool file, or RECEIVE the whole file to your A disk. There is online help for all these commands. If you have an external security manager, you would also want to look at those spool files in a similar manner, since those facilities can sometimes bring the OS to its knees. The hardware console should save any system abend codes if they are generated. Did you check for hardware failure? Ray Mrohs US DOJ From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Kreiter, Chuck Sent: Monday, September 21, 2009 2:24 PM To: IBMVM@LISTSERV.UARK.EDU Subject: z/VM Stopped Responding Last week, while I was out of the office, we had our first unplanned z/VM outage. We are running z/VM 5.3 with about 20 guests. Symptoms were that a user tried to access a Linux guest to do a production code move around 10:00 PM. He was unable to get in. Then, the operators received lightening bolt messages and nothing on z/VM or any of the Linux systems were available. The ultimate resolution was to re-IPL. All was fine afterwards. My dilemma is that I'm not accustomed to debugging z/VM. I'd really like to look at the system logs for that time to see if there are any messages. I know that can be done, but for the life of me can not find any procedures to do it. Any help would be greatly appreciated. Thanks, Chuck Kreiter State Auto Insurance
Re: z/VM Stopped Responding
On Monday, 09/21/2009 at 02:48 EDT, Kreiter, Chuck chuck.krei...@stateauto.com wrote: Thanks Alan. I don't know what was done other than a LOAD so I'm not sure we got a dump. Should I open a PMR to get assistance on viewing operators console logs? Without a dump there's not much we can do for you, sorry. I would suggest that you should update your local procedures manual to indicate that any emergency IPL of a sick system should be via System Restart, not Load or Load Clear. The easiest way to get assistance looking at console logs, etc. is right here. In fact, the advice is alredy rolling in! :-) Alan Altmark z/VM Development IBM Endicott
Re: z/VM Stopped Responding
Thanks for the note. I did check for hardware failures, but nothing is on the HMC. From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Mrohs, Ray Sent: Monday, September 21, 2009 2:51 PM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: z/VM Stopped Responding The real ultimate solution would have been to do a restart dump so that IBM could take a look at what was last happening on your system. Hopefully your OPERATOR id has its console output spooled to someplace. Type Q R OPERATOR or Q P OPERATOR. If you don't have VM:Spool, you need to get those spool file(s) 'owned' by your userid via the TRANSFER command. Then either PEEK the spool file, or RECEIVE the whole file to your A disk. There is online help for all these commands. If you have an external security manager, you would also want to look at those spool files in a similar manner, since those facilities can sometimes bring the OS to its knees. The hardware console should save any system abend codes if they are generated. Did you check for hardware failure? Ray Mrohs US DOJ From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Kreiter, Chuck Sent: Monday, September 21, 2009 2:24 PM To: IBMVM@LISTSERV.UARK.EDU Subject: z/VM Stopped Responding Last week, while I was out of the office, we had our first unplanned z/VM outage. We are running z/VM 5.3 with about 20 guests. Symptoms were that a user tried to access a Linux guest to do a production code move around 10:00 PM. He was unable to get in. Then, the operators received lightening bolt messages and nothing on z/VM or any of the Linux systems were available. The ultimate resolution was to re-IPL. All was fine afterwards. My dilemma is that I'm not accustomed to debugging z/VM. I'd really like to look at the system logs for that time to see if there are any messages. I know that can be done, but for the life of me can not find any procedures to do it. Any help would be greatly appreciated. Thanks, Chuck Kreiter State Auto Insurance
