Numerical argument out of domain

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This article is a part of the Troubleshooting collection.

Problem

XXX User:Dustin: RAIT Device in Device API does not return these errors!

Other languages: English


You have a RAIT setup, and amcheck(8) (and many other commands) return an error like:

$ amcheck test
...
amcheck-server: slot 2: reading label: Numerical argument out of domain

Explanation

The EDOM error (Numerical argument out of domain) points to an XOR sum mismatch when reading a RAIT set.

That could result when you have a read error on the one of the members of the RAIT set that was not flagged by the individual tape drive.

More frequently however you inserted the wrong tape in one of the drives and one of the members of the RAIT does not have the correct label, matching the other members.

Solution

To find out which member (apart from looking on the handwritten labels on the physical tapes themselves), you must use ammt and amdd to extract the first file from each member tape. Let's suppose you have a RAIT setup with chg-multi, and the contents of slot 2 are:

 slot 2  rait:{file:/amandatapes/daily/vtape2,/dev/nst0}

Then get the label of each member of the RAIT:

$ ammt -t file:/amandatapes/daily/vtape2 rewind
$ amdd  if=file:/amandatapes/daily/vtape2 bs=32k count=1
AMANDA: TAPESTART DATE X TAPE DAILY-02

1+0 in
1+0 out
$ ammt -t file:/amandatapes/daily/vtape2 rewind
$ ammt -t /dev/nst0 rewind
$ amdd  if=/dev/nst0 bs=32k count=1
AMANDA: TAPESTART DATE X TAPE Test-03

1+0 in
1+0 out
$ ammt -t /dev/nst0 rewind

In the above example, member 1 (a vtape) has a tape labeled "DAILY-02" in slot 2, while the physical tapedrive has a tape labeled "Test-03". You need to find the physical tape labeled "DAILY-02" and insert that in the drive.

If both claim to be same tape, then you could have a hardware fault in one of the drives resulting the XOR sum mismatch, and the RAIT driver could not rebuild the data from the other streams.

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