[HECnet] DECnet-RT?

I haven?t used this particular CDROM so I can only speculate, but here are a couple of things that might help ? RT11 has an architectural limit of 32Mb per file system. Most disk drives, even way back then, are bigger than that and have to be partitioned if you want to use all the space. This is an RT11 thing, not a CDROM nor a PDP-11 nor a simh, feature. I assume the first partition on the CDROM is bootable. You?d CDROM image to simh as a rq device and boot it. Once RT11 is running, you can use the RT11 ?SET DUn UNIT=n PART=n? command to assign the other DUn units to partitions on the same CDROM. Check the RT11 commands manual for a description of the SET DU command. Hope that helps, It?s kind of vague, I know, but I haven?t used these CDROM images. Bob *From:* owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] *On Behalf Of *Peter Allan *Sent:* Tuesday, March 31, 2020 4:26 AM *To:* hecnet at update.uu.se *Subject:* Re: [HECnet] DECnet-RT? Thanks to Ray, I now have the v1 and v5 of the RT-11 CD (well, the ISO file of it). However, I am confused by the nature of the virtual CD. I have extracted the file RTV5RL.03 and started an installation using it. I have not continued with the installation, but it looks like it should work.So far,so good. However, the file README.1st refers to there being several RT11 partitions on the CD and that some of these are bootable. I have never come across multiple partitions on a CD and I don't know how to access them. The SIMH ATTACH command appears to only connect to files, not partitions on a disk. So I am stuck. Any suggestions? Peter Allan