The following files and folders have been uploaded to the Files area of the [email protected] group.
By: Harold Grovesteen <h.grovsteen@...>
Description:
Sample of SATK stand-alone dump tool output. Includes the assembly of the bare-metal program that was dumped.
|
Re: Virtual Machine Memory
Thanks!
On 3/27/24 10:16, Dave Wade wrote:
toggle quoted message
Show quoted text
Harold,
I
think I turned attachments off. Just create a temp folder in
the files section and upload, then only those who need it
download it.
Dave
?
?
Thanks so much for your responses.
My first question, can the VM's memory contents be
"extracted" from the virtual machine and this content be moved
from the VM system for processing is in fact possible.? Is it
worth doing?? It is clear if I were to go in that direction,
it would be a separate utility.
As is frequent with such questions, the concept got expanded
somewhat.? Happy to see it stimulated a few "grey/gray cells".
?
I appreciate the suggestion of how to do this with a VM
system.? However, I do not have a running VM system.? I gave
up all personal interest in system administration of all sorts
by the time I retired.? If someone is willing to produce such
a dump in a form my Linux PC could read, I would appreciate
it.? If not I understand that too.? It would give me an idea
of whether this separate utility might be worth looking at
developing.
Just a little background:
I have been working on a bare-metal development system (SATK)
used outside of a mainframe.? My frustrations working on
OpenSolaris support in Hercules drove me to realizing this
tool would be of value.? A lot of Hercules tests now use
SATK.? My work with QEMU finally drove me to work on closing
the loop by producing a memory dump for this development
system.
This is unlike your usual experience where everything is
developed within VM (CMS), run on VM, and the output examined
on VM.? In the SATK environment the bare-metal program is
build outside the mainframe, loaded into it, and the output's
destination, in this case a dump, is also outside the
mainframe, the PC.
Again, thanks so much.? I have a fully working version for
the S/370 world.? Does anyone know if this list supports
attachments?
Harold Grovesteen
On 3/27/24 04:07, Frank D. Engel, Jr.
wrote:
Wondering if the proposed new command could actually be
added at the CP level instead of the CMS/MVS level.
CP might save the state of the machine to a prepared
location in DASD then restore it when the user next logs in,
essentially mimicking the VMWare (for example)
suspend/restore capability.? Users can already disconnect
and leave the machine intact to reconnect to it later (even
leaving it running in the background), so from a user
perspective this would extend that with the option to
reconnect to it even after a shutdown / re-ipl of VM, but
without leaving it running in between.
There would obviously be limits to this when working with
dedicated hardware, but for virtualized hardware as with a
typical CMS machine, I would think it could be done (granted
with a fair amount of effort)?
?
On 3/27/24 00:23, Bertram Moshier
wrote:
Hello Harold,
What you desire doesn't exist in
VM/370 today, but it is possible.? Cray Supercomputers
are real memory systems that use swapping to allow
multiple users to use the same real memory space.? IBM
went with paging for its solution to this problem.?
Seymore Cray rejected this method because it added
around seven cycles?to each operation
referencing?memory.
Let us see if I understand you
correctly.? You want to take a snapshot of a virtual
machine's memory (e.g., 0 to maximum storage size of
the machine).? How you accomplish this depends upon
what you want to do with the image and the memory
methodology used by the users' virtual machine
operating system.
There are two methods for
collecting a copy of the memory for offline
examination.? They are:
1) Copy the state of the virtual
machine to a binary file.? What we used for the Cray
IBM VM Station. When an error occurred, the station
would dump all of its memory, registers, etc., to a
file. We had tools to examine the station and even
run it to the point of failure. (We would use the
internal trace to simulate the interrupts and data
transmissions (to and from the Cray and users'
virtual machines).) This improved the station's
stability?so we could catch coding and design issues
before shipping the product to customers.
2)? You could (as Bob suggested)
use the existing CP DUMP command.? A better solution
would be to allow CP to dump the data more than the
printer.
On the other hand, if you want to
stop and restart an operating system without regard to
space or time and support both paging and swapping,
you will need to add a new command to the operating
system. This would be similar to Windows hibernation
but with more functionality.? As this new command is
at the operating system level (e.g., MVS), it would
support both real and virtual environments.
?
?
For my
Stand Alone Tool Kit project I am working on the
ability to
create a formatted memory dump.? It depends upon
preserving the
machine's memory in a host (Windows, Linux, etc.)
platform's host file
system.? With Hercules this is accomplished using the
Hercules command
'savecore'.
SATK is sometimes used with z/VM virtual machines.?
So, I am asking:
is it possible to transfer the contents of a virtual
machine's physical
(absolute storage) memory out of VM (any version,
VM/370 or z/VM) in any
manner at all?
The assumption is that a bare-metal program has been
executing within
the virtual machine, so CMS is out of the picture.?
This would strictly
be CP commands as I understand things.
Assuming the storage contents exists outside of the
virtual machine,
whatever format that turns out to be, can be
manipulated for use by the
dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from
within the
virtual machine embedded within the bare-metal program
if required to
get the memory content out of the virtual machine, BUT
only if that is
the only way.
Asking the experts...
Harold Grovesteen
|
Re: Virtual Machine Memory
Harold, I think I turned attachments off. Just create a temp folder in the files section and upload, then only those who need it download it. Dave ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Harold Grovesteen
Sent: Wednesday, March 27, 2024 2:58 PM
To: [email protected]
Subject: Re: [h390-vm] Virtual Machine Memory? Thanks so much for your responses. My first question, can the VM's memory contents be "extracted" from the virtual machine and this content be moved from the VM system for processing is in fact possible.? Is it worth doing?? It is clear if I were to go in that direction, it would be a separate utility. As is frequent with such questions, the concept got expanded somewhat.? Happy to see it stimulated a few "grey/gray cells". ? I appreciate the suggestion of how to do this with a VM system.? However, I do not have a running VM system.? I gave up all personal interest in system administration of all sorts by the time I retired.? If someone is willing to produce such a dump in a form my Linux PC could read, I would appreciate it.? If not I understand that too.? It would give me an idea of whether this separate utility might be worth looking at developing. Just a little background: I have been working on a bare-metal development system (SATK) used outside of a mainframe.? My frustrations working on OpenSolaris support in Hercules drove me to realizing this tool would be of value.? A lot of Hercules tests now use SATK.? My work with QEMU finally drove me to work on closing the loop by producing a memory dump for this development system. This is unlike your usual experience where everything is developed within VM (CMS), run on VM, and the output examined on VM.? In the SATK environment the bare-metal program is build outside the mainframe, loaded into it, and the output's destination, in this case a dump, is also outside the mainframe, the PC. Again, thanks so much.? I have a fully working version for the S/370 world.? Does anyone know if this list supports attachments? Harold Grovesteen On 3/27/24 04:07, Frank D. Engel, Jr. wrote: Wondering if the proposed new command could actually be added at the CP level instead of the CMS/MVS level. CP might save the state of the machine to a prepared location in DASD then restore it when the user next logs in, essentially mimicking the VMWare (for example) suspend/restore capability.? Users can already disconnect and leave the machine intact to reconnect to it later (even leaving it running in the background), so from a user perspective this would extend that with the option to reconnect to it even after a shutdown / re-ipl of VM, but without leaving it running in between. There would obviously be limits to this when working with dedicated hardware, but for virtualized hardware as with a typical CMS machine, I would think it could be done (granted with a fair amount of effort)? ? On 3/27/24 00:23, Bertram Moshier wrote: Hello Harold, What you desire doesn't exist in VM/370 today, but it is possible.? Cray Supercomputers are real memory systems that use swapping to allow multiple users to use the same real memory space.? IBM went with paging for its solution to this problem.? Seymore Cray rejected this method because it added around seven cycles?to each operation referencing?memory. Let us see if I understand you correctly.? You want to take a snapshot of a virtual machine's memory (e.g., 0 to maximum storage size of the machine).? How you accomplish this depends upon what you want to do with the image and the memory methodology used by the users' virtual machine operating system. There are two methods for collecting a copy of the memory for offline examination.? They are: 1) Copy the state of the virtual machine to a binary file.? What we used for the Cray IBM VM Station. When an error occurred, the station would dump all of its memory, registers, etc., to a file. We had tools to examine the station and even run it to the point of failure. (We would use the internal trace to simulate the interrupts and data transmissions (to and from the Cray and users' virtual machines).) This improved the station's stability?so we could catch coding and design issues before shipping the product to customers. 2)? You could (as Bob suggested) use the existing CP DUMP command.? A better solution would be to allow CP to dump the data more than the printer.
On the other hand, if you want to stop and restart an operating system without regard to space or time and support both paging and swapping, you will need to add a new command to the operating system. This would be similar to Windows hibernation but with more functionality.? As this new command is at the operating system level (e.g., MVS), it would support both real and virtual environments. ? ? For my Stand Alone Tool Kit project I am working on the ability to
create a formatted memory dump.? It depends upon preserving the
machine's memory in a host (Windows, Linux, etc.) platform's host file
system.? With Hercules this is accomplished using the Hercules command
'savecore'.
SATK is sometimes used with z/VM virtual machines.? So, I am asking:
is it possible to transfer the contents of a virtual machine's physical
(absolute storage) memory out of VM (any version, VM/370 or z/VM) in any
manner at all?
The assumption is that a bare-metal program has been executing within
the virtual machine, so CMS is out of the picture.? This would strictly
be CP commands as I understand things.
Assuming the storage contents exists outside of the virtual machine,
whatever format that turns out to be, can be manipulated for use by the
dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from within the
virtual machine embedded within the bare-metal program if required to
get the memory content out of the virtual machine, BUT only if that is
the only way.
Asking the experts...
Harold Grovesteen
|
Re: Virtual Machine Memory
Thanks so much for your responses.
My first question, can the VM's memory contents be "extracted"
from the virtual machine and this content be moved from the VM
system for processing is in fact possible.? Is it worth doing?? It
is clear if I were to go in that direction, it would be a separate
utility.
As is frequent with such questions, the concept got expanded
somewhat.? Happy to see it stimulated a few "grey/gray cells". ?
I appreciate the suggestion of how to do this with a VM system.?
However, I do not have a running VM system.? I gave up all
personal interest in system administration of all sorts by the
time I retired.? If someone is willing to produce such a dump in a
form my Linux PC could read, I would appreciate it.? If not I
understand that too.? It would give me an idea of whether this
separate utility might be worth looking at developing.
Just a little background:
I have been working on a bare-metal development system (SATK)
used outside of a mainframe.? My frustrations working on
OpenSolaris support in Hercules drove me to realizing this tool
would be of value.? A lot of Hercules tests now use SATK.? My work
with QEMU finally drove me to work on closing the loop by
producing a memory dump for this development system.
This is unlike your usual experience where everything is
developed within VM (CMS), run on VM, and the output examined on
VM.? In the SATK environment the bare-metal program is build
outside the mainframe, loaded into it, and the output's
destination, in this case a dump, is also outside the mainframe,
the PC.
Again, thanks so much.? I have a fully working version for the
S/370 world.? Does anyone know if this list supports attachments?
Harold Grovesteen
On 3/27/24 04:07, Frank D. Engel, Jr.
wrote:
toggle quoted message
Show quoted text
Wondering if the proposed new command could actually be added
at the CP level instead of the CMS/MVS level.
CP might save the state of the machine to a prepared location
in DASD then restore it when the user next logs in, essentially
mimicking the VMWare (for example) suspend/restore capability.?
Users can already disconnect and leave the machine intact to
reconnect to it later (even leaving it running in the
background), so from a user perspective this would extend that
with the option to reconnect to it even after a shutdown /
re-ipl of VM, but without leaving it running in between.
There would obviously be limits to this when working with
dedicated hardware, but for virtualized hardware as with a
typical CMS machine, I would think it could be done (granted
with a fair amount of effort)?
On 3/27/24 00:23, Bertram Moshier
wrote:
Hello Harold,
What you desire doesn't exist in VM/370 today, but it is
possible.? Cray Supercomputers are real memory systems that
use swapping to allow multiple users to use the same real
memory space.? IBM went with paging for its solution to this
problem.? Seymore Cray rejected this method because it added
around seven cycles?to each operation referencing?memory.
Let us see if I understand you correctly.? You want to
take a snapshot of a virtual machine's memory (e.g., 0 to
maximum storage size of the machine).? How you accomplish
this depends upon what you want to do with the image and the
memory methodology used by the users' virtual machine
operating system.
There are two methods for collecting a copy of the memory
for offline examination.? They are:
1) Copy the state of the virtual machine to a binary
file.? What we used for the Cray IBM VM Station. When an
error occurred, the station would dump all of its memory,
registers, etc., to a file. We had tools to examine the
station and even run it to the point of failure. (We would
use the internal trace to simulate the interrupts and data
transmissions (to and from the Cray and users' virtual
machines).) This improved the station's stability?so we
could catch coding and design issues before shipping the
product to customers.
2)? You could (as Bob suggested) use the existing CP
DUMP command.? A better solution would be to allow CP to
dump the data more than the printer.
On the other hand, if you want to stop and restart an
operating system without regard to space or time and support
both paging and swapping, you will need to add a new command
to the operating system. This would be similar to Windows
hibernation but with more functionality.? As this new
command is at the operating system level (e.g., MVS), it
would support both real and virtual environments.
Bertram Moshir
WB8ERT
For
my Stand Alone Tool Kit project I am working on the ability
to
create a formatted memory dump.? It depends upon preserving
the
machine's memory in a host (Windows, Linux, etc.) platform's
host file
system.? With Hercules this is accomplished using the
Hercules command
'savecore'.
SATK is sometimes used with z/VM virtual machines.? So, I am
asking:
is it possible to transfer the contents of a virtual
machine's physical
(absolute storage) memory out of VM (any version, VM/370 or
z/VM) in any
manner at all?
The assumption is that a bare-metal program has been
executing within
the virtual machine, so CMS is out of the picture.? This
would strictly
be CP commands as I understand things.
Assuming the storage contents exists outside of the virtual
machine,
whatever format that turns out to be, can be manipulated for
use by the
dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from
within the
virtual machine embedded within the bare-metal program if
required to
get the memory content out of the virtual machine, BUT only
if that is
the only way.
Asking the experts...
Harold Grovesteen
|
Re: Virtual Machine Memory
Wondering if the proposed new command could actually be added at
the CP level instead of the CMS/MVS level.
CP might save the state of the machine to a prepared location in
DASD then restore it when the user next logs in, essentially
mimicking the VMWare (for example) suspend/restore capability.?
Users can already disconnect and leave the machine intact to
reconnect to it later (even leaving it running in the background),
so from a user perspective this would extend that with the option
to reconnect to it even after a shutdown / re-ipl of VM, but
without leaving it running in between.
There would obviously be limits to this when working with
dedicated hardware, but for virtualized hardware as with a typical
CMS machine, I would think it could be done (granted with a fair
amount of effort)?
On 3/27/24 00:23, Bertram Moshier
wrote:
toggle quoted message
Show quoted text
Hello Harold,
What you desire doesn't exist in VM/370 today, but it is
possible.? Cray Supercomputers are real memory systems that
use swapping to allow multiple users to use the same real
memory space.? IBM went with paging for its solution to this
problem.? Seymore Cray rejected this method because it added
around seven cycles?to each operation referencing?memory.
Let us see if I understand you correctly.? You want to take
a snapshot of a virtual machine's memory (e.g., 0 to maximum
storage size of the machine).? How you accomplish this depends
upon what you want to do with the image and the memory
methodology used by the users' virtual machine operating
system.
There are two methods for collecting a copy of the memory
for offline examination.? They are:
1) Copy the state of the virtual machine to a binary
file.? What we used for the Cray IBM VM Station. When an
error occurred, the station would dump all of its memory,
registers, etc., to a file. We had tools to examine the
station and even run it to the point of failure. (We would
use the internal trace to simulate the interrupts and data
transmissions (to and from the Cray and users' virtual
machines).) This improved the station's stability?so we
could catch coding and design issues before shipping the
product to customers.
2)? You could (as Bob suggested) use the existing CP DUMP
command.? A better solution would be to allow CP to dump the
data more than the printer.
On the other hand, if you want to stop and restart an
operating system without regard to space or time and support
both paging and swapping, you will need to add a new command
to the operating system. This would be similar to Windows
hibernation but with more functionality.? As this new command
is at the operating system level (e.g., MVS), it would support
both real and virtual environments.
Bertram Moshir
WB8ERT
For
my Stand Alone Tool Kit project I am working on the ability to
create a formatted memory dump.? It depends upon preserving
the
machine's memory in a host (Windows, Linux, etc.) platform's
host file
system.? With Hercules this is accomplished using the Hercules
command
'savecore'.
SATK is sometimes used with z/VM virtual machines.? So, I am
asking:
is it possible to transfer the contents of a virtual machine's
physical
(absolute storage) memory out of VM (any version, VM/370 or
z/VM) in any
manner at all?
The assumption is that a bare-metal program has been executing
within
the virtual machine, so CMS is out of the picture.? This would
strictly
be CP commands as I understand things.
Assuming the storage contents exists outside of the virtual
machine,
whatever format that turns out to be, can be manipulated for
use by the
dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from within
the
virtual machine embedded within the bare-metal program if
required to
get the memory content out of the virtual machine, BUT only if
that is
the only way.
Asking the experts...
Harold Grovesteen
|
Re: Virtual Machine Memory
Hello Harold,
What you desire doesn't exist in VM/370 today, but it is possible.? Cray Supercomputers are real memory systems that use swapping to allow multiple users to use the same real memory space.? IBM went with paging for its solution to this problem.? Seymore Cray rejected this method because it added around seven cycles?to each operation referencing?memory.
Let us see if I understand you correctly.? You want to take a snapshot of a virtual machine's memory (e.g., 0 to maximum storage size of the machine).? How you accomplish this depends upon what you want to do with the image and the memory methodology used by the users' virtual machine operating system.
There are two methods for collecting a copy of the memory for offline examination.? They are:
1) Copy the state of the virtual machine to a binary file.? What we used for the Cray IBM VM Station. When an error occurred, the station would dump all of its memory, registers, etc., to a file. We had tools to examine the station and even run it to the point of failure. (We would use the internal trace to simulate the interrupts and data transmissions (to and from the Cray and users' virtual machines).) This improved the station's stability?so we could catch coding and design issues before shipping the product to customers.
2)? You could (as Bob suggested) use the existing CP DUMP command.? A better solution would be to allow CP to dump the data more than the printer.
On the other hand, if you want to stop and restart an operating system without regard to space or time and support both paging and swapping, you will need to add a new command to the operating system. This would be similar to Windows hibernation but with more functionality.? As this new command is at the operating system level (e.g., MVS), it would support both real and virtual environments.
Bertram Moshir WB8ERT
For my Stand Alone Tool Kit project I am working on the ability to
create a formatted memory dump.? It depends upon preserving the
machine's memory in a host (Windows, Linux, etc.) platform's host file
system.? With Hercules this is accomplished using the Hercules command
'savecore'.
SATK is sometimes used with z/VM virtual machines.? So, I am asking:
is it possible to transfer the contents of a virtual machine's physical
(absolute storage) memory out of VM (any version, VM/370 or z/VM) in any
manner at all?
The assumption is that a bare-metal program has been executing within
the virtual machine, so CMS is out of the picture.? This would strictly
be CP commands as I understand things.
Assuming the storage contents exists outside of the virtual machine,
whatever format that turns out to be, can be manipulated for use by the
dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from within the
virtual machine embedded within the bare-metal program if required to
get the memory content out of the virtual machine, BUT only if that is
the only way.
Asking the experts...
Harold Grovesteen
|
Re: Virtual Machine Memory
Hi Harold,
All versions of VM, from VM/370 through z/VM support the CP DUMP command.? This command dumps virtual machine storage to the virtual machine's printer.? The issuer of the command can specify an address and length to be dumped, including the entire virtual machine storage area.
Since the dump content is printed, it is in character form, not raw binary.? It is a formatted dump, in essence.? The format of the printed dump varies a bit for the different versions of VM to account for architecture differences (for example dumping 24 vs 31 bit addresses) but they are largely similar.
Since the dump is written to the virtual printer, the output of the CP DUMP command ends up in the VM spool.? You could read the spool file back into a virtual machine for manipulation using i/o commands to the virtual reader, or you could use the DIAGNOSE X'14' spool interface to read it (present in all versions), or you could read it back in using CMS and the READCARD command.
Since the dump is formatted and depending on your needs, you may have to reconvert the formatted data back into a binary form.? Not a difficult exercise but as you said, a separate problem for later.
If you wish to see what one of these dumps looks like, here is an example set of command to obtain a small dump, and read it back into the virtual machine so you can use CMS to review it.? Logon to a CMS userid and issue:
1. SPOOL PRT *
2. CP DUMP 0.2000
3. CLOSE PRT
4. READ DUMP OUTPUT
5. browse or edit the DUMP OUTPUT file to view the contents.
This will dump your virtual machine storage from location 0 for X'2000' bytes.? Just enough for a nice sample.
Regards,
Bob
|
Re: Virtual Machine Memory
Harold,
? ?It probably won't be what you are looking for, but back in the early 80's, I fooled around with the SAVESYS command to save images of DOS release 27.? However, they were fairly useless since when reloaded, the system was unaware of any pending interrupts that had been in progress at the time of the SAVESYS.? SAVESYS, if I remember correctly, is more traditionally used with discontinguous shared segments, so I was pushing the envelope by trying to use them for DOS virtual machines.
? ?Downloading recent z/VM manuals just now, there seems to be setup required to use SAVESYS.
? ?I haven't intensively used VM since 1983, just occasional application work at systems software companies, ending in 1996.??
? ? ? ? Allan
|
For my Stand Alone Tool Kit project I am working on the ability to create a formatted memory dump.? It depends upon preserving the machine's memory in a host (Windows, Linux, etc.) platform's host file system.? With Hercules this is accomplished using the Hercules command 'savecore'.
SATK is sometimes used with z/VM virtual machines.? So, I am asking:
is it possible to transfer the contents of a virtual machine's physical (absolute storage) memory out of VM (any version, VM/370 or z/VM) in any manner at all?
The assumption is that a bare-metal program has been executing within the virtual machine, so CMS is out of the picture.? This would strictly be CP commands as I understand things.
Assuming the storage contents exists outside of the virtual machine, whatever format that turns out to be, can be manipulated for use by the dump program.? Separate problem for later.
Note, I am not opposed to a programmatic approach from within the virtual machine embedded within the bare-metal program if required to get the memory content out of the virtual machine, BUT only if that is the only way.
Asking the experts...
Harold Grovesteen
|
Re: Reconnect to MVS Console
Thanks for the additional detail.
|
Re: Reconnect to MVS Console
Hello,
You'll reconnect to the MVS console no matter the run setting.? The run setting allows the virtual machine to continue running regardless of the state of the console.? The default is RUN OFF, which means to NOT allow the virtual machine to operate, when the console is in a CP READ.? If run is ON, the virtual machine (for you MVS) can continue to function.
The following paraphrased is from the CP Command Reference Guide for General Users:
The SET RUN ON/OFF command controls whether the virtual machine stops when the attention key is pressed or upon reconnection to a disconnected virtual machine.
Set run ON allows you to activate the attention key (causing a read of a CP command) without stopping your virtual machine. When the CP command is entered, it is immediately executed and the virtual machine resumes execution. OFF places the virtual machine in the normal CP environment, so that when the attention key is pressed, the virtual machine stops. When you log on VM/SP, RUN is set off.?
For your purposes the PA1 button is part of the reconection process of VM.? Unless run is on, you'll fall into a? rEAD and MVS will not run until you do the BEGIN command (B).
Bertram Moshier WB8ERT
Hi Bertram:
I have the machine IPL via the directory entry.
I can confirm reconnecting even without the #CP SET RUN ON.
Interestingly, if I do a #CP Q SET is shows RUN is OFF.
|
Re: Reconnect to MVS Console
On Thu, Mar 21, 2024 at 05:18 PM, Daniel L. Srebnick wrote:
I can confirm reconnecting even without the #CP SET RUN ON.
If you SET RUN ON, you shouldn't need to BEGIN when you reconnect. Cheers, Rene FERLAND, Montreal
|
Re: Reconnect to MVS Console
Hi Bertram:
I have the machine IPL via the directory entry.
I can confirm reconnecting even without the #CP SET RUN ON.
Interestingly, if I do a #CP Q SET is shows RUN is OFF.
|
Re: Reconnect to MVS Console
Hello,
To have MVS running upon reconnecting to the MVS console you need to set run on (#CP SET RUN ON) before disconnecting from the console.
I'm not sure how you start MVS.? I can think of two methods:
?1) USER DIRECT directive of IPL <drive number> ?2) A script (EXEC, EXEC2, or BREXX) to set up the virtual machine to run MVS and the start MVS (e.g., CP IPL <drive letter>).
If it is number two, you could set run on (CP SET RUN ON) in the script.
If it is number one, you'll need to manually issue both the set run on and disconnect commands manually.? You can combine CP commands.? An example is:? #CP SET RUN ON #CP DISC
I hooe the above thoughts help you.? Please let us on this forum know how it turns out.
Thank you,
Bertram Moshier WB8ERT
Ah, that is right, it kept running with #CP DISC.
And BEGIN is what I needed.? Confirming that works.
Thanks Dave.
|
Re: Reconnect to MVS Console
Ah, that is right, it kept running with #CP DISC.
And BEGIN is what I needed.? Confirming that works.
Thanks Dave.
|
Re: Reconnect to MVS Console
If you enter #CP LOGOFF you logoff the MVS machine. You need #CP DISC to leave it running. To reconnect just logon to the ID you are using to run MVS. You usually then need to enter ¡°BEGIN¡±¡ ? Dave ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Daniel L. Srebnick via groups.io
Sent: Thursday, March 21, 2024 9:23 PM
To: [email protected]
Subject: [h390-vm] Reconnect to MVS Console? I'm running MVS as a guest under VM/370.? If I #CP LOGOFF to disconnect, the MVS system keeps running.? At some point, I want to logon mvs to reconnect to the console.? However, when I logon, the console is not present and I am in a CP session.
What can I do to get back the console?
Or, if I am asking the wrong question, how do I best disconnect from the MVS operator console which MVS keeps running and reconnect to it later?
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I'm running MVS as a guest under VM/370.? If I #CP LOGOFF to disconnect, the MVS system keeps running.? At some point, I want to logon mvs to reconnect to the console.? However, when I logon, the console is not present and I am in a CP session.
What can I do to get back the console?
Or, if I am asking the wrong question, how do I best disconnect from the MVS operator console which MVS keeps running and reconnect to it later?
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Re: BREXX DO loop counting weirdness
My recollection is that issue is about argument processing, but the fix makes sure the segment is up to date. Please perform the procedure to save the segment.? I will be away all day tomorrow for appointments, and check status later tomorrow afternoon.? (EST)
On Sat, Mar 16, 2024 at 10:16?AM Ross Patterson via <ross.patterson= [email protected]> wrote: On Sat, Mar 16, 2024 at 10:08 Bob Bolch < bob@...> wrote: If the code could be posted in an issue, I could try to reproduce the error here.
Will do.
For anyone who's curious about this bug, it's now being tracked as VM/370 CE Issue #96 (), and I've been able to thin the testcase down to the barest of bones, and still get it to fail at least occasionally:
I'll hold off posting here any further, unless we figure out what's wrong.
Ross
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Re: BREXX DO loop counting weirdness
On Sat, Mar 16, 2024 at 10:16?AM Ross Patterson via <ross.patterson= [email protected]> wrote: On Sat, Mar 16, 2024 at 10:08 Bob Bolch < bob@...> wrote: If the code could be posted in an issue, I could try to reproduce the error here.
Will do.
For anyone who's curious about this bug, it's now being tracked as VM/370 CE Issue #96 (), and I've been able to thin the testcase down to the barest of bones, and still get it to fail at least occasionally:
I'll hold off posting here any further, unless we figure out what's wrong.
Ross
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On Sat, Mar 16, 2024 at 02:36 PM, Fish Fish wrote:
BOTTOM LINE: with some guests (most notably VM/370) you will *always* an "error" reported whenever a tape drive unloads a tape, since, as explained in the README above, a UC (Unit Check) is *required* to be presented in such a situation, and it is nothing to worry about. It's completely normal in the Hercules environment.
Thank you for the explanation. ?... Mark S.
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Ren¨¦ Ferland
Mark A. Stevens