Source:Using slu topology for detecting devices

Overview

slu topology is a SEP sesam SCSI loader utility that provides information about the loaders and drives connected to the system; it also shows their relation which is required to identify unique IDs of tape drives and configure them by using SEP sesam GUI.

Using slu topology

1. To be able to run the SEP sesam commands globally, you must set up a profile as described in FAQ: What happens when I set a profile?
2. To list all attached SCSI devices, run slu topology:
<SESAM_BIN>/sesam/slu topology If the devices are properly connected, you should get the output similar to the one shown below.

3. By examining the output you are able to determine the correct names of loaders and tape drives; in the latter case, you can also determine the connection between the drive name and the drive number sequence. This is important if you are using persistent naming for tape devices. For more details on when to use persistence and how to configure it, see Enabling persistent naming for tape devices.
   Each tape drive is listed in a separate line with its name (Tapexxx) and its relation to the pre-set drive number in the loader; this pre-set drive number is the last in the line and specifies the number of the tape drive in the loader as referenced by SEP sesam. SEP sesam assigns a number to each tape drive, starting with 0 (0: the first tape drive in the loader; 1: the second tape drive in the loader ...). The equivalent GUI field is named the Drive No. in loader.
For example, from the above output you can read the following characteristics that are required for (re-)configuration of loaders and drives in GUI: Loader: HP MSL6000 Series 3G3ALRT572VN (Changer0) Drive: HP Ultrium 4-SCSI HU18111L60 (Tape2147483644) (adr=480) 0 Drive: HP Ultrium 4-SCSI HU18111L66 (Tape2147483643) (adr=481) 1 Drive: HP Ultrium 4-SCSI HU18141PP1 (Tape2147483645) (adr=483) 3 In our example, the tape drive with the persistent name Tape2147483644 relates to drive number 0 (the first tape drive in the loader). You enter the unique tape drive name, e.g., Tape2147483644, when (re)configuring your backup hardware in GUI.
4. You can also check the number of slots in the loader. SEP sesam numbers the slots from 0 to the number of cartridges in the loader.

In our example, the loader has 56 slots (0–55) and a port slot which is not configured in SEP sesam.

By using slu topology you can check whether your hardware is properly configured and recognized by SEP sesam. If the device is not listed, SEP sesam auto-detection was not successful. The cause may be trivial, for example, your device driver is not installed correctly. In such cases, you have to install the missing driver and then manually configure your storage hardware. In other rare cases, the connection between loader and drives cannot be recognized automatically and you have to manually configure your storage hardware. For detailed steps on how to manually (re-)confingure your loaders and tape drives, see Configuring Loaders and Drives.