Re: Optical disk as raw disk?

In <2796k1INN4te@emory.mathcs.emory.edu> cynthia@hpsgcip1.sgp.hp.com (Cynthia Leong) writes: >Hi netters, >I'm planning to use the Optical Disk as raw disk for my Online engine. >The informix tech support personnel told me that as long as my system >support it, I can use it in place of the scsi hardisk. What I expect (s)he meant was "as long as your system makes it look the same as a scsi hard disk". >Performance is not an issue because the optical disk acts as a online >archive store.I've the HP Optical Disk Library System Model 20 which >is a autochanger that gives me a capacity of 20GB. How do you make an autochanger look like a scsi disk? What's going to tell it to change platters??? OnLine won't! >Has anyone experienced setting up this library system? >I have some query concerning the setup .... > - is the creation of the device file the same as the scsi hardisk? > ie mknod , chown and grp to informix, chmod 660 etc > The Library system has two optical drive with addr 4 & 5. These > drive's addr is internal, I guess. Since the Library is a scsi > device and for the host system to communicate with it is through > its scsi addr, how can the host specifically talk to each drive? > - Can I partition the optical disk like scsi hardisk? > ie have several optical disks as one dbspace and on. > (I have slots for 32 pieces of optical disk) These are opsys and driver issues not Informix ones. OnLine would need your system to make it look as if it was dealing with ordinary, magnetic, continuously online, read/write, owner informix, group informix, mode 660 raw chunks. If your opsys/drivers/drive combo can do this, then you would stand a chance of making it work, but I suspect that the autochanger blows it. graeme -- Disclaimer: The author's opinions are his own, and not necessarily those of Pyramid Technology Ltd. or Pyramid Technology Inc. --------------------------------------------------------------------------- -m------- Graeme Sargent Voice: +44 (0)252 373035 ---mmm----- Senior Database Consultant Fax : +44 (0)252 373135 -----mmmmm--- Pyramid Technology Ltd. Telex: Tell who??? -------mmmmmmm- Farnborough, Hants GU14 7PL Email: graeme@pyra.co.uk --------------------------------------------------------------------------- We have the technology. The tricky bit is learning how to use it.