Storagetek L20 (Sdlt drives) AIX 4.3

[v279]

Is it possible to use hardware compression on this jukebox with sdlt drives on AIX 4.3. Bull tells us that this is not possible, we should us software compression......


Thanks

Tom

 

[fpastano]

Hi, the HW compression is enabled on the sdlt and is not related to the type of jukebox you are using.
on AIX is only necessary to use the special devices that enable the compression mode, and automatically the chip on the sdlt enable the feature.

hi

 

[v279]

Thanks Fpastano,

Which device files should be used and where to get it ??

Tom

 

[fpastano]

soory, I must correct myself, the exact procedure to enable the compression is this:

Data Compression
Setting the Data Compression attribute (for chdev, the compress attribute) to yes causes the tape drive to be in compress mode, if the drive is capable of compressing data. If so, then the drive writes data to the tape in compressed format so that more data fits on a single tape. Setting this attribute to no forces the tape drive to write in native mode (noncompressed). Read operations are not affected by the setting of this attribute. The default setting is yes.

You must use the chdev command and enable the compression on the device.

Hi

 

[v279]

Result:

chdev -l rmt1 -a compress=yes
Method error (/etc/methods/chggen):
0514-017 The following attributes are not valid for the
specified device:
compress

Idem for rmt2. I think the drives should be used compressed

What to do ??

Tom.