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We have a tape library which is connected to a server by SAS link. Server is running OS Linux. OS doesn't see the tape library in /proc/scsi/scsi . We tried to rescan scsi bus(*1), but it didn't help.

What could we do to access it?

PS:The main goal is just to see it connected to the server We also have storage system connected to the same HBA. Servers,storage and library vendor - HP.

*1 - for each host we run echo '- - -' > /sys/class/scsi_host/hostN/scan

st0ne_c0ld
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  • 1) You need to provide the output from dmesg, specifically check if the tape drive was detected at all. 2) with this being RHEL5 you may well need to install the Firmware for the tape drive into check the vendor website for linux specific firmware/drivers and install accordingly. – Oneiroi Jun 27 '12 at 10:39
  • 1. /var/log/messages and dmesg are clean. 2. I will check HP website, but documentation says that it should be visible without any additional actions... – st0ne_c0ld Jun 27 '12 at 10:58

2 Answers2

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I'd like to see more detail. Please provide the server model, tape drive information and explain how it is onnected to the server. Which backup software suite will you be using?

In general, a SAS tape device should be connected to a dedicated SAS HBA. In most HP installations, this is really an LSI-based controller, so you'd be working with the mptfusion set of drivers. So grep -i mpt in your dmesg output and the relevant log files in /var/log...

If the driver/module is loaded, you don't need to rescan or do anything manual to recognize the drive.

This may be different if you're connected directly to an HP Smart Array controller... So please clarify.

ewwhite
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We rebooted the server and tape library appear in /proc/scsi/scsi and /dev/ files created properly. It is not the way it should work. But it helped.

Probably it is because of SAS "topology map" or something like this. Because after reboot - multipathd stopped showing error messages about disconnected links.(we also tried to reload multipathd before reboot) Looks like HBA or driver remember what is in HBA ports until reboot.

st0ne_c0ld
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