DEC Alpha Notes

Kernel mods are not necessary. They are, however, useful for debugging studio/mps hardware problems because that's the only way for the computer to print out a list of what's on the chain. More on kernel mods later. For now, let me show you what's required:

Go into /dev as root.


  1. Run "./MAKEDEV tzX" where X is the scsi ID of the mps. This will create the next available rmt devices. Digital unix doesn't really care what the numbers are so it assigns them in numerical order. So, if this is the first tape drive you're installing on this system, the device names are going to be rmt0x where x is either 'a', 'h', 'l', or 'm' (auto, high, low, or medium densities, for studio, use high). If it's the second tape drive, the MAKEDEV command will make rmt1x devices.


  2. Look at the devices you just created and their major and minor numbers. You will notice that the "high density, auto-rewind" device has a minor number of X * 1024 where 'X' is the scsi ID of the device (ie. 4096 for scsi ID 4). Keep this in mind for the next step.


  3. To make the printer tape device on the studio, add 128 to the minor device number and use that to make another device. For example, if /dev/rmt0h had a major number of 9 and a minor number of 4096, you would execute the following command to create the printer device:

    mknod /dev/rmt0_2h c 9 4224
    chmod 666 /dev/rmt0_2h


  4. For mountback (pre-CD Studio+; legacy CD Studio only), the idea is the same except you only add 64 to the minor number. If /dev/rz4a had a major number of 8 and a minor number of 4096, then you would create the mountback device by doing:

    For the block devices:
    mknod /dev/rz4_1a b 8 4160
    chmod 600 /dev/rz4_1a

    For the character(raw) devices:
    mknod /dev/rrz4_1a b 8 4160
    chmod 600 /dev/rrz4_1a



Kernel Modifications

The following is only necessary if you feel the Studio isn't being seen or some other scsi-id number related problem. Go into /sys/conf and copy the current configuration file to some new name. This is a lot like the SunOS portion of a kernel config. Add the devices that correspond to the Studio or MPS. A good example if a Studio is at scsi ID 4:

device disk


at scsi0

drive 33

device tape


at scsi0

drive 32

device tape


at scsi0

drive 34

Note that the two tape device names are the same. This is not a typo. You will also find that if there's a hard drive configured at ID 4, that will have the same name as your mountback device.

Run "./config". "cd" to "../{kernel_name}" and type make. You now have a kernel that will show the device names at boot time. Save the old kernel and move the new kernel into place and reboot. Keep in mind that the alpha doesn't show the device names on the screen forever. They are, however, kept in the /var/adm/messages log file (if the system logging hasn't been changed).

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