Device : read n bytes, expected block size of n

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Q. On random new and re-used tapes, I infrequently get a message that looks like this:</B> [date] [time] nsrd: media notice : volume "TMX017" on device

 "/dev/rmt/3cbn": read 4 bytes, expected block size of 131072, check
 system device configuration, disabling forward space record

A. This appears to be a strictly Solaris issue, and requires modifying the st.conf file. Information on . Arthur Darren Dunhan posted (26 April 2000): Every, every time I've seen this, it's been a bad st.conf file. I could absolutely reproduce it by restoring from a tape. The error *persists* even after you've fixed the st.conf for reading older tapes saved under the previous version. After the tapes get recycled, the problems go away. While this is usually reported for servers running under Solaris, and points to settings in the st.conf file (information on how to do this can be found in section 8), a similar error message was reported involving Networker running on NT with a Netware client: The error message that I am getting is: device "\\.\Tape0" read 32768 bytes, expected block size 65536,

 check system device configuration. The backup has completed
 successfully.

Joe posted (15 April 2000) the following solution: As the message suggested, I believe you have device configuration all or new tapes, or setup a 32kb block device and mark it as read only. You can then use this device for recovering the old tapes (32kb). For the old tape, you have to manually scrach the tape (override the label) and relabel it on 64kb block device. PS. upgrade to sp4 may resolve the hanging issue too, because there is a new tcpip and thread shipped.