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IBM RT PC experts?

MattisLind

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Yes. That is identical to what mine did. I successfully used a GOTEK with FlashFloppy firmware.

I learnt a bit about the VRM Maintenance Facility from the IBM RT PC Problem Determination Guide. It can be started from VRM floppy 1.

In there it was possible to list the contents of the filesystems on the disk.

Indeed this machine has been used for CAD work. There is directories named CATIA in there.

iaLyGgVl.jpg


hd0 is definetely the root filesystem, but I cannot figure out why it refuses to boot from the disk or why it refuses to IPL hd0 using the VRM Maintenance Facility.
 

MattisLind

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The VRM Maintenance Facility has a format command that I would like to try out with an empty drive. It let you specify all drive params including precomp cylinder which is kind of interesting since this is only needed for ST505 type of drives. ESDI should’t need it since all that is handled on the drive in ESDI. This sounds like low level format to me. I wonder what happens if an IDE disk is installed. An IDE disk should ignore attempts to do LLF, right?
 

snuci

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I ran the format command on my drive. You can run it to show the geometry and it looked correct. You can then get out of format before actually doing it.

I was able to see my filesystems. Here is a picture. Note my hd6 "mini disk" has a VRM attribute. I don't know if it's good or bad and I see don't see anything similar on yours. I am reading more of the Problem Determination Guide before I break something.

IMG-3912 (Medium).JPG
 
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bear

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It may just be that somebody erased (or simply renamed) the kernel, or otherwise did something like an rm -rf / on the system, which would just as effectively render the system unusable. I suppose it may be possible to use the AIX floppies to boot a maintenance shell you can use to mount the disks, similar to how AIX/6000 works, but honestly I haven't tried it and it's been an age since I even installed AIX. There are several "extra" minidisks present on your install and I would be curious to find out whether anything interesting were left there before wiping the disk out to reinstall it.
 

bear

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good spot, the hd6 "VRM" minidisk is missing, so yes, at a minimum, that is going to prevent the system from automatically IPLing. Not sure why it isn't booting once the VRM is loaded from floppy, but it may be that the VRM hasn't loaded all the necessary drivers for AIX, or who knows, possibly even that the paging (pgsp) minidisk is missing too. I wonder if the 310 MB disk was installed later as an upgrade, and VRM and the paging space were left on the 70 MB disk?

It's _also_ also possible that the AIX install has some record of its former console device and is unhappy that it is not present, or at least not using the newly installed megapel for it. AIX/6000 works this way, but ISTR once upon a time when I replaced my 6155 Enhanced Monochrome display adapter with a Megapel, that it worked fine immediately. It's possible the 5080 is different. I wouldn't bet my life on it though.

These are guesses. I have no special insight yet into what you might be running into.
 

bear

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or there could be read errors under /unix or /etc/init or the handful of other files needed for AIX to IPL.
 

MattisLind

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Aha. The VRM missing was indeed a good spot! There are two empty spaces on my disk. Perhaps I could just add VRM and PGSP there. They are quite large so maybe it could fit. Is 10000 ok for VRM? And then 29000 for PGSP. Sounds reasonable to me.
There is an option on the VRM floppy menu to update the VRM. I could try that one.

@snuci I thought that the diagnostic program told that your disk C was dead? But then you could do a format and then all the mindisks suddenly were visible? Or was this the D drive?
 

snuci

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Diagnostics didn't say the drive is dead, it just said there was a problem. When I run the VRM diskette, I see this bottom error message when I get to the menu. I'd love to check out the file systems but I don't see an easy option to check them. Still looking into it. Maybe my /vrm is damaged and hence why I cannot boot. I am still looking into it.

BTW: My hard drive has been opened before as the top screw holes were exposed. That does make me wonder if I will be able to save this drive.

VRM_RW_Error (Medium).JPG
 

MattisLind

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Aha. Interesting. I wonder if I should re-install the E70 drive and see if VRM is able to detect it? But I have a feeling that my E70 is dead.

Anyhow my plan is now to add the VRM and PGSP minidisks to the H310 disk. It looks like those were deleted in 1992 on my drive.Perhaps they got a E70 drive that they put VRM and PGSP on? And now that one is not accessible / dead?

I think I have an idea on how to add the minidisks using the VRM Maintenance Facility. Then probably need to set the attributes of the minidisk. Hopefully it is just to do an install of VRM using the menu system after that.
 

MattisLind

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Added the SWAP and VRM minidisks successfully. Used settattr to set VRM attribute on the VRM disk and then managed to install VRM successfully.

It now goes past LED indicator 22 and jumps among many different values. Finally it ends up toggling between 25 and C6. Nothing more happens. I found this explanation:

C6 is "VRM dump waiting for diskette to be inserted. the 'c6' will alternate on the LEDs with the VRM abend code. After the diskette has been inserted, a keyboard sequence is used to start the dump."
25 is "The VRM could not find a disk device driver."

That sounds bad. I wonder if there might be some kind of incompatibility between the VRM I installed (from bitsavers) and the AIX kernel? I could try the other set of VRM floppies on bitsavers.

But other than that all suggestions what to do is highly appreciated.
 
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snuci

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That is progress.

Did you use the B25 VRM floppies? I think that is newer (because it's bigger) and I am pretty sure I am not using those VRM floppies myself. Maybe the older one doesn't have driver for the larger disk? Most documentation doesn't even mention the H310 hard drive. Just a thought.
 

MattisLind

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Yes. Progress indeed!

I first tried the B25 floppies and they were no go. Then I tried the other set and that worked!

Now it is booting into AIX 2.2.1. It complains a bit of missing 5080 Attachment Adapter and token ring not working but I get the login prompt. But how can I break into it?

Getting into single user somehow? Editing /etc/passwd somehow?

DCYthQKl.jpg
 

MattisLind

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BTW. The keyboard is highly annoying. It is marked 6487679 on the back and is a Swedish / Finnish variant. It is a rubber dome keyboard and it is nearly impossible to type on. The keys sticks in the down position for quite some time and you need to press hard to get a keypress. Is there anything that could be done to make the keyboard happier? Or it is just old rubber?
 

snuci

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Getting into single user somehow? Editing /etc/passwd somehow?

You can edit files with the VRM Maintenance Facility, right?

BTW. The keyboard is highly annoying. It is marked 6487679 on the back and is a Swedish / Finnish variant. It is a rubber dome keyboard and it is nearly impossible to type on. The keys sticks in the down position for quite some time and you need to press hard to get a keypress. Is there anything that could be done to make the keyboard happier? Or it is just old rubber?

Luckily, I have both keyboards. I have one of the rubber dome ones (but it is new I think) and I have a buckling spring Model M keyboard (part no 1392366) which is the one I am using. Needless to say, it's awesome. You may have to take apart your keyboard and clean the rubber dome layer. Maybe someone spilled something on it at some point or the rubber has not aged well.

RT_Keyboard (Medium).JPGr

Now in my case, I think my hard drive is toast. Every time I run a command that accesses the hard disk, I get an error as below. I don't know how I am getting the minidisk/filesystem table properly. It probably needs a low level format as it's running otherwise, from the noises it makes. That would, however, mean that I could not save this drive so I have found another H310 on eBay yesterday evening and purchased it. I will put this away until I get the drive and see if there are similar issues. If so, maybe it's not the drive but the HD controller card?


VRM_IO_Error (Medium).JPG
 

MattisLind

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Lucky you! A buckling spring RT keyboard would be nice. I have a model M but it a standard one unfortuantely. The RT seems to have a specific ID code and then also the speaker built in. Otherwise it looks like the scan codes are very similar.

I have researched the /etc/passwd a bit and come to the conclusion that the disk to boot is the Install / Maintenance disk. It should give a Single user prompt where one could mount the disk and then run vi on the /etc/passwd file. Will gave that procedure a try tomorrow.

I am not really sure that there is a good way to edit files in the VRM Maintenance Facility. On the other hand one should be able to copy files. So copy the file and then edit it off line and copy it back could be a solution perhaps.
 

MattisLind

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B1792609-B39C-4147-8C6F-5316128B05CF.jpeg

I am in! I used the Installation /Maintenance disk. Then selected option 3 to start a stand alone shell, mounted /dev/hd0 and then edited /etc/security/passwd (not /etc/passwd). I removed the password for the root user and left it as ”password = ”. Rebooted and was able to login without password.

There seems to be some kind of problems with minidisk hd9. It gives read errors and fails fsck. I think this is where the users had their home directories.
 

MattisLind

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I did some experimenting adding one of those old multi-IO ISA boards.

Adding the multi-IO board as a secondary disk with floppy disabled (and all other serial, parallell and games ports disabled as well) didn't work very well. It complained about floppy jumper settings was wrong somehow.

Removing the ESDI adapter entirely and just keep the multi-IO board gave a bit of positive result. It was possible to start the VRM bootable disk and format a 128 MByte CF disk. It formatted successfully and the it was possible to install VRM onto it. Unfortunately trying tio start the Install / Maintenance disk to install AIX failed. It looked like it read the disk but then after reading up to track 79 it just hanged.

Trying to run the diagnostic gave the "02" blinking code, which meant VRM Read Error.

I also tried a 4 Gigabyte CF card but that wasn't even possible to start the VRM boot floppy with that CF disk attached.

It seems that an old ISA IDE controller with CF cards is not working at least. Haven't tried with real IDE disks yet.
 

MattisLind

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I have a stash of IDE disks which I set out to try. The first disk was a 6 gig IDE disk. It refused to work at all with the RT PC.

Then I tested a 1 gig disk. It was working much better. I took ages to format but the VRM installed without a hitch.

Next step was to use the Install /Maintenance disk to install the OS. Previously with the CF card it hanged when the install program has read in. But now the install program started up!

It then successfully installed the base system on to the 1 gig IDE disk. I restarted the machine and it booted AIX 2.2.1 nicely!

So no need for old big clunky ESDI disks!

I will do some more research into which other IDE diska in my stash of old disks are working on thw RT tomorrow.

Any ide on why CF card isn’t working while the ordinary IDE disk did? I was under the impression that CF cards emulated IDE closely.
 

Al Kossow

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What model 1g drive worked?
Can you tell what kind of ISA controller it thinks the IDE drive is?

There have been lots of CF cards made so who knows how closely the ones you tried match what
the RT expects a supported controller to respond to.

Depending on how far you want to dig into it, you may have to trace the commands going to the
working IDE drive and see how they differ from what happens with the CF

Also, if you have one an ISA card that is only an IDE adapter would be interesting to try.
 
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