When you start the virtual machine the disk will be visible to the OS. If you can't see it, you will need to force a rescan for SCSI devices. There are two methods to achieve this. The first involves echoing wildcards to the individual SCSI host(s). Default Linux I/O multipathd configuration, SCSI timeout and Oracle RAC caveat. I’ve been recently involved in a project to migrate from old and rusty Cisco MDS 9222i to the new MDS 9506 SAN switches and during the first phase of the migration the primary node in a two-node Oracle RAC cluster lost access to its voting disks and went down.
Block volumes attached with the iSCSI attachment type use the iSCSI protocol to connect a volume to an instance. See Volume Attachment Types for more information about volume attachment options.
- LUN Rescan usig 'rescan-scsi-bus.sh' fails, Server can not Identify New Added/Removed LUN (Doc ID 2114242.1) Last updated on SEPTEMBER 01, 2020. Applies to: Linux OS - Version Oracle Linux 6.0 and later Oracle Cloud Infrastructure - Version N/A and later Linux x86-64 Linux x86 Symptoms. LUNs were deleted from the Server.
- I found this great definition of the SCSI3-PR on “dba-oracle.com” “SCSI-3 PR, which stands for Persistent Reservation, supports multiple nodes accessing a device while at the same time blocking access to other nodes.
Once the volume is attached , you need to log on to the instance and use the iscsiadm command-line tool to configure the iSCSI connection. After you configure the volume, you can mount it and use it like a normal hard drive.
To enhance security, Oracle enforces an iSCSI security protocol called CHAP that provides authentication between the instance and volume.
Accessing a Volume's iSCSI Information
When you successfully attach a volume to an instance, Block Volume provides a list of iSCSI information. You need the following information from the list when you connect the instance to the volume.
- IP address
- Port
- CHAP user name and password (if enabled)
- IQN
The CHAP credentials are auto-generated by the system and cannot be changed. They are also unique to their assigned volume/instance pair and cannot be used to authenticated another volume/instance pair.
Oracle Scsi & Raid Devices Driver Updater
The Console provides this information on the details page of the volume's attached instance. Click the Actions icon (three dots) on your volume's row, and then click iSCSI Information. The system also returns this information when the AttachVolume API operation completes successfully. You can re-run the operation with the same parameter values to review the information.
Oracle Scsi & Raid Devices Drivers
See Attaching a Volume and Connecting to a Volume for step-by-step instructions.