SAS Device Miswire

What Caused the Problem?

The storage array contains an improper connection from the source enclosure to the expansion enclosure(s). The Recovery Guru Details area provides specific information you will need as you follow the Recovery Steps.

Important Notes

Depending on the nature of the miswire, you may not have redundant access to the expansion enclosures. A RAID controller module failure could result in a loss of access to your data. You should correct this problem as soon as possible.
The details area provides information about what type of miswire was detected. The miswire types are: invalid SAS topology, EMM miswire, or Host connection miswire. The expansion enclosures must be cabled in the supported configuration.

The following examples are provided to help you to diagnose your miswire problem. However, your cabling configuration may differ from the examples.

Invalid SAS Topology - This miswire condition occurs when you connect the Out ports of two EMMs in different expansion enclosures. You should only connect Out ports of an EMM to an In port of an EMM in a different enclosure.

Example 1: Invalid SAS Topology

1. RAID Enclosure
2. Expansion Enclosure

EMM Miswire - This miswire condition occurs when you connect the Out port of an EMM to the In port of the other EMM in the same enclosure. You should not connect EMMs in the same enclosure together.

Example 2: EMM Miswire

1. RAID Enclosure
2. Expansion Enclosure

Host Channel Miswire - This miswire condition occurs when you connect a Host Channel to another port on the RAID enclosure or a port on another expansion enclosure. You should only connect Host Channels to an appropriate HBA or other external device.

Example 3: Host Channel Miswire

1. RAID Enclosure
2. Expansion Enclosure

Host Adapter Miswire - This miswire condition occurs when you connect an external Host Adapter port to any port other than a Host Channel port (EMM In port, or EMM Out port). You should only connect a Host Adapter port to a Host Channel port on a controller.

Important: If a Host Adapter Miswire is reported, the port on the controller or EMM that is connected to the HBA will not be able to connect to any device until after the cabling is corrected and the controller or EMM is power-cycled.

Example 4: Host Adapter Miswire

1. RAID Enclosure
2. Expansion Enclosure
3. Host

Recovery Steps

Use the information provided in the Recovery Guru Details area to determine which port is the origin of the miswire. Using this information, trace the cable that is attached to the miswired channel or port to the connector on the other end.

Refer to your cabling documentation to reconnect the cable to the appropriate port. It may be necessary for you to reconnect more than one cable in order to have a valid configuration.

Once you have a valid cabling configuration, go to step 3.

Check the Details area to see which type of miswire is being reported.

If...	Then...
The miswire type is: Invalid SAS Topology EMM Miswire Host Channel Miswire	Go to step 5.
The miswire type is "Host Adapter Miswire"	Go to step 4.

Check the Details area to see whether the miswired port is on an EMM or a controller.

If...

Then...

The port is on a controller

The controller must be removed and reseated in order to power-cycle the controller.

a	From the Support tab, click the Manage Controllers link.
b	Click the Place Controller Online or Offline link.
c	Place the controller listed in the Details area Offline.
d	Click the Recheck button to rerun the Recovery Guru. There should be an Offline controller problem reported in the Summary area.
e	Follow the Offline Controller Recovery Steps, ONLY until you have removed the controller. Disregard any references to new or replacement controllers. After you have removed the controller, do not continue with the Offline Controller Recovery steps until you are instructed to do so.
f	Reinsert the controller.
g	Complete the rest of the Offline Controller Recovery Steps. Once you have completed the Offline Controller Recovery Steps, go to step 5.

The port is on an EMM

a	Stop all I/O to the storage array.
b	Physically locate the expansion enclosure that contains the EMM listed in the Details area.
c	Turn off power to all power supply/fan modules in the expansion enclosure.
d	Wait 30 seconds, and then turn on power to all power supply/fan modules in the expansion enclosure.
e	Go to step 5.

Click the Recheck button to rerun the Recovery Guru. The failure should no longer appear in the Summary area. If the failure appears again, contact your technical support representative.

If you stopped I/O to the storage array in step 4, resume I/O.

Note: Additional information on this issue may be available. Please visit the Dell support website at support.dell.com and select your product model. Choose "troubleshooting" as your tool option, then search by this procedure title.