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Adding new LUN on Linux without reboot

We had a small problem today, where we wanted to add a few LUNs to a (backup) Linux server without rebooting. The problem was that the qlogic qle2460 did see the LUN but the OS wouldn't assign it a SCSI device ID (i.e. /dev/sdg or /dev/sdr or so). We needed to figure out a way to rescan the LUNs on the HBA and force a detection of LUNs in the OS layer.
A new colleague solved it by using /sys, issuing a LIP and doing what is also pointed out in the old mail archive from Dell: New LUN available on Linux without reboot. Good to know. Thanks Dell and Koen!

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