Explanation
The cluster has detected that it does not have
sufficient redundancy in its connections to the disk controllers.
This means that another failure in the SAN could result in loss of
access to the application data. The cluster SAN environment should
have redundant connections to every disk controller. This redundancy
allows for continued operation when there is a failure in one of the
SAN components.
To provide recommended redundancy, a cluster
should be configured so that:
- each node can access each disk controller through two or more
different initiator ports on the node.
- each node can access each disk controller through two or more
different controller target ports. Note: Some disk controllers
only provide a single target port.
- each node can access each disk controller target port through
at least one initiator port on the node.
If there are no higher-priority errors being reported, this
error usually indicates a problem with the SAN design, a problem with
the SAN zoning or a problem with the disk controller.
If there
are unfixed higher-priority errors that relate to the SAN or to disk
controllers, those errors should be fixed before resolving this error
because they might indicate the reason for the lack of redundancy.
Error codes that must be fixed first are:
- 1210 Local FC port excluded
- 1230 Login has been excluded
Note: This error can be reported if the required action,
to rescan the Fibre Channel network
for new MDisks, has not been performed after a deliberate reconfiguration
of a disk controller or after SAN rezoning.
The 1627 error code
is reported for a number of different error IDs. The error ID indicates
the area where there is a lack of redundancy. The data reported in
an event log entry indicates where the condition was found.
The
meaning of the error IDs is shown below. For each error ID the most
likely reason for the condition is given. If the problem is not found
in the suggested areas, check the configuration and state of all of
the SAN components (switches, controllers, disks, cables and cluster)
to determine where there is a single point of failure.
010040
A disk controller is only accessible from a single node port.
- A node has detected that it only has a connection to the disk
controller through exactly one initiator port, and more than one initiator
port is operational.
- The error data indicates the device WWNN and the WWPN of the connected
port.
- A zoning issue or a Fibre Channel connection
hardware fault might cause this condition.
010041 A disk controller is only accessible from a single
port on the controller.
- A node has detected that it is only connected to exactly one target
port on a disk controller, and more than one target port connection
is expected.
- The error data indicates the WWPN of the disk controller port
that is connected.
- A zoning issue or a Fibre Channel connection
hardware fault might cause this condition.
010042 Only a single port on a disk controller is accessible
from every node in the cluster.
- Only a single port on a disk controller is accessible to every
node when there are multiple ports on the controller that could be
connected.
- The error data indicates the WWPN of the disk controller port
that is connected.
- A zoning issue or a Fibre Channel connection
hardware fault might cause this condition.
010043 A disk controller is accessible through only half,
or less, of the previously configured controller ports.
- Although there might still be multiple ports that are accessible
on the disk controller, a hardware component of the controller might
have failed or one of the SAN fabrics has failed such that the operational
system configuration has been reduced to a single point of failure.
- The error data indicates a port on the disk controller that is
still connected, and also lists controller ports that are expected
but that are not connected.
- A disk controller issue, switch hardware issue, zoning issue or
cable fault might cause this condition.
010044 A disk controller is not accessible from a node.
- A node has detected that it has no access to a disk controller.
The controller is still accessible from the partner node in the I/O
group, so its data is still accessible to the host applications.
- The error data indicates the WWPN of the missing disk controller.
- A zoning issue or a cabling error might cause this condition.