thank you for telling me so much.> and it can't mount by:
i use ./MAKEDEV hd3
settrans -cp /cdrom /hurd/isofs /dev/hd3
to set my cdrom,
mount /cdrom
> it tells me unknown filesystem or device
The Hurd replaces the concept of mount by the conept of translators.
If you have set a translator you don't have to mount any more. Mount is just a (somtime not working) wrapper script for settrans.
but i can cd into /cdrom and do every things normally.
Yes, your translator settings semm to work.
but the next time i boot hurd , it can't be used whatever i try (such as mount or boot with the cd in the cdrom ,etc)
Strange. > how can i do?
Read The GNU/Hurd User's Guide from the Documentation Section in www.gnu.org/software/hurd .
Read about showtrans, try showtrans on /cdrom.
If you still have problems, give us the output of showtrans.
Patrick -- Engineers motto: cheap, good, fast: choose any two Patrick Strasser <pstrasser at sbox dot tugraz dot at> Student of Telematik, Techn. University Graz, Austria

