ANTX5123W
I/O REQUEST FOR DEVICE device_number HAS TIMED OUT, FUNC= function_code

Explanation

I/O for device device_number did not complete in the allotted time. This message can result when a storage control session has a large enough number of updated records in cache that it cannot process a read or a write I/O without affecting the application, or if there are no paths available to the device. If XRC is running in a channel extender environment, this error can indicate that an extended line-outage condition has occurred.

The I/O can be a read or a write command, either from primary volumes or to secondary volumes. The reason for the error, by function_code, is as follows:
function_code
Description
1
Creating a storage control session
2
Adding a volume to a storage control session during volume initialization, or changing device blocking threshold.
3
Reading tracks during volume synchronization
4
Writing tracks during volume synchronization
5
Reading updated records from a storage control session
6
Writing updated records to a secondary volume
7
Removing a volume from a storage control session
8
Ending a storage control session
9
Retrieving storage control session information
10
Suspending a volume
11 – 15
Retrieving storage control session information
17
Retrieving storage control session information
18
Retrieving storage control session bitmap for a device
20
Adding a volume to a storage control session during volume resynchronization
21
Changing device blocking threshold.
22
I/O timeout retrieving write pacing information

System action

The operation that is doing the I/O is failed. If the I/O is associated with data movement, XRC can suspend volumes as a result. XQUERY report data fields can also contain asterisks for data that could not be retrieved from the storage control.

System programmer response

Use the DEVSERV command to determine and correct the cause of the delay to XRC I/O operations.

Source

Extended remote copy (XRC).