Cisco MDS SanOS Troubleshooting Guide -- Troubleshooting Mixed Generation Hardware

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Revision as of 14:22, 20 July 2010

This section describes how to identify and resolve problems that might occur in the mixed generation hardware components of the Cisco MDS 9000 Family. It includes the following sections:

Overview

The below table identifies the modules supported by the Cisco MDS 9500 Series switches and Cisco MDS 9216A and Cisco MDS 9216i switches, as well as the Generation 2 switches:

Table 5-1 Generation 2 Modules and Switches

Note:

Generation 2 Fibre Channel switching modules are not supported on the Cisco MDS 9216 switch; however, they are supported by both the Supervisor-1 module and the Supervisor-2 module.

The 4-port 10-Gbps Fibre Channel switching module supports 10-Gbps port rates. The rest of the Generation 2 modules support 1-Gbps, 2-Gbps, 4-Gbps, or autosensing port rates.

For detailed information about the installation and specifications for these modules, refer to the hardware installation guide or the Configuration guides at the following website:

http://cisco.com/en/US/products/ps5989/tsd_products_support_series_home.html.

Port Groups

Each module has four groups of one or more ports in port groups that share common resources, such as bandwidth and buffer credits. The table below shows the port groups for the Generation 2 Fibre Channel switches and modules.

Table 5-2 Bandwidth and Port Groups for Generation 2 Modules

Note:

Port groups are defined by the hardware and consist of sequential ports. For example, ports 1 through 12, ports 13 through 24, ports 25 through 36, and ports 37 through 48 are the port groups on the 48-port 4-Gbps Fibre Channel switching modules.

Port Speed Mode

The table below shows the port speeds allowed on each Generation 2 switching module.

Dynamic Bandwidth Management

Note:

When migrating a host only supporting up to 2-Gbps traffic to the 4-Gbps switching modules, use autosensing with 2-Gbps maximum bandwidth.

Note:

The 4-port 10-Gbps switching module only supports 10-Gbps links.

Out-of-Service Interfaces

You can take interfaces out of service to release shared resources that are needed for dedicated bandwidth. This feature is especially useful for the 48-port 4-Gbps switching modules. When an interface is taken out of service, all shared resources are released and made available to the other interface in the port group or module.

Caution:

If you need to bring an interface back into service, you might disrupt traffic if you need to release shared resources from other interfaces.

Port Index Availability

Each chassis in the Cisco MDS 9000 Series has a hardware-based maximum port availability based on internally assigned port indexes. When the maximum number of port indexes is reached in a chassis, any modules remaining or added to the chassis will not boot up. The number of physical ports on a Fibre Channel module is equal to its number of port indexes. However, for Gigabit Ethernet modules (IPS-8, IPS-4, and MPS-14/2), one physical port is equal to four port indexes (one port index for iSCSI and three port indexes for FC IP tunnels). Table 5-6 lists the physical ports and port indexes (virtual ports) allocated per Cisco MDS 9000 module.

Using any combination of modules that include a Generation 1 module or a Supervisor-1 module limits the port index availability to 252 on all Cisco MDS 9500 Series directors. Generation 1 modules also require contiguous port indexes where the system assigns a block of port index numbers contiguously starting from the first port index reserved for the slot that the module is inserted in (See Table 5-7). This means that while there may be enough port indexes available for a Generation 1 module, the module may not boot up because the available port indexes are not in a contiguous range or the contiguous block does not start at the first port index for a given slot.

Example 5-1 shows a case with a Supervisor-1 module, where a 48-port Generation 2 module borrowed port indexes from the first slot. Slot 1 still has 16 port indexes available, but the full 32 indexes are no longer available (28-31 are used by the module in slot 4). This means that no Generation 1 module except a 16-port Fibre Channel switching module can be inserted into slot 1 because some of the port indexes for the slot are already in use.

Example 5-1 Borrowing Port Indexes from Another Slot </p>

 switch#show port index-allocation
Module index distribution:
---------------------------------------------------+
Slot   | Allowed |      Alloted indices info       |
       |  range* | Total |          Index values   |
-------|---------|-------|-------------------------|
1      |   0-  31|   -   |   -                     |
2      |  32-  63|   32  |   32-63                 |
3      |  64-  95|   48  |   64-95,224-239         |
4      |  96- 127|   48  |  96-127, 240-252, 28-31 |
7      | 128- 159|   32  |   128-159               |
8      | 160- 191|   32  | 160-191                 |
9      | 192- 223|   32  | 192-223                 |
SU     | 253-255 |   3   |  253-255                |
*Allowed range applicable only for Generation-1 modules . 

Combining Modules and Supervisors

Initial Troubleshooting Checklist

Generation 1 and Generation 2 Issues

Module Does Not Come Online

Verifying Port Index Allocation Using Device Manager

Verifying Port Index Allocation Using the CLI

Cannot Configure Port in Dedicated Mode

Verifying Bandwidth Utilization in a Port Group Using Device Manager

Verifying Bandwidth Utilization in a Port Group Using the CLI

Cannot Enable a Port

Cannot Upgrade Supervisor System Image

Selecting the Correct Software Images