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Mauli
Asked: 2011-10-11 23:45:48 +0800 CST

What happens if I pull the plug of an iSCSI device?

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If I pull the network connector of an iSCSI device, what happens? Will the "client" automatically connect again if I plug it in again? Is there a timeout?

(in my case I'm talking about a QNAP NAS which provides the iSCSI disk and a Ubuntu Server which mounts it)

linux iscsi network-attached-storage qnap

1 Answers

  1. Best Answer

    If the network connection dies, the iSCSI initiator will start to see time-outs due to not being able to contact the target. After a certain amount of time, the OS will start to see reads from the disk timing out and cached writes fail to be flushed to the disk. The timeout period where the initiator notices an issue and passes it back up to the SCSI queue is configurable - see http://www.open-iscsi.org/docs/README for the open-iscsi (section 8.1.1).

    I believe most initiators will attempt to reconnect to devices that have previously been unreachable. There was an option in Microsoft's s/w initiator to allow a 'non-persistent' connection, but I never really found that particularly useful.

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