Cisco MDS 9000 Family Switch-to-Switch Interoperability Configuration Guide
Interoperability Limitations

Table Of Contents

Interoperability Limitations

Cisco MDS 9000 Family

Standard Interoperability Mode Limitations

Legacy Switch Interoperability Modes (2 and 3)

Legacy Switch Interoperability Mode 4

Inter-VSAN Routing (IVR)

McData Switches

Brocade Switches


Interoperability Limitations


This chapter describes the restrictions and limitations imposed on specific vendor switches when working in interoperability mode. It includes the following sections:

Cisco MDS 9000 Family

McData Switches

Brocade Switches

Cisco MDS 9000 Family

The standard interoperability mode, which has been a fully functional feature since MDS SAN-OS Release 1.0(1), enables the MDS 9000 switch to interoperate with Brocade and McData switches when they are configured for interoperability. The standard interoperability mode allows the MDS 9000 switch to communicate over a standard set of protocols with these vendor switches.


Note The MDS 9020 switch does not support individual interop modes. To see how to interoperate the MDS 9020 with third-party switches, see "MDS 9020 Switch Interoperability."


Standard Interoperability Mode Limitations

When a VSAN is configured for the default interoperability mode, the MDS 9000 Family of switches is limited in the following areas when interoperating with non-MDS switches:

Interop mode only affects the specified VSAN. The MDS 9000 switch can still operate with full functionality in other non-interop mode VSANs. All switches that partake in the interoperable VSAN should have that VSAN set to interop mode, even if they do not have any end devices.

Domain IDs are restricted to the 97 to 127 range, to accommodate McData's nominal restriction to this same range. Domain IDs can either be set up statically (the MDS 9000 switch will only accept one domain ID; if it does not get that domain ID, it isolates itself from the fabric), or preferred (if the MDS 9000 switch does not get the requested domain ID, it takes any other domain ID).

TE ports and PortChannels cannot be used to connect an MDS 9000 switch to a non-MDS switch. Only E ports can be used to connect an MDS 9000 switch to a non-MDS switch. However, TE ports and PortChannels can still be used to connect an MDS 9000 switch to other MDS 9000 switches, even when in interop mode.

Only the active zone set is distributed to other switches.

In MDS SAN-OS Release 1.3(x), Fibre Channel timers can be set on a per VSAN basis. Modifying the times, however, requires the VSAN to be suspended. Prior to SAN-OS Release 1.3, modifying timers required all VSANs across the switch to be put into the suspended state.

If a Brocade switch issues a cfgsave command, the MDS 9000 switch rejects this vendor specific command. The full zone database on the MDS 9000 switch is not updated. You must manually update the full zone database or copy the active zone set to the full zone database.

The MDS 9000 switch still supports the following zoning limits per switch across all VSANs:

2000 zones (as of SAN-OS 3.0, 8000 zones)

20000 aliases

1000 zone sets

20000 members

8000 LUN members

256 LUN members per zone/alias


Note Before configuring this number of zones in a mixed environment, determine the maximum number that can be supported by the other vendors present in the environment.


Table 2-1 provides a summary of features and behaviors in standard interop mode for an MDS 9000 switch.

Table 2-1 Summary of Features in Standard Interop Mode for an MDS 9000 Switch 

Feature
Requirement / Behavior

Minimum Firmware Level

1.0(1) standard interop mode.

VSANs

Only the VSANs explicitly set for interop mode are affected. All others maintain their independence.

High Availability

Fully redundant dual supervisor modules maintain full functionality.

Domains

Domain IDs are restricted to the 97 to 127 range.

PortChannels and TE Ports

They can still be used to directly connect two MDS 9000 switches together, even while in interop mode. However, they cannot be used to directly connect to a non-MDS 9000 switch. Standard E ports are required to connect to non-MDS switches.

Zones and Zone Sets

Only the active zone set is propagated. Up to 2000 zones (8000 for SANOS 3.0+) can be supported by the MDS 9000 switch. The default zone policy changes to deny.

Fabric Manager and Device Manager

They can still be used to fully manage the MDS 9000 switch, and to create zones to be distributed to the non-MDS platforms. Fabric Manager can still view the entire mixed topology.

Security

SSH, Telnet, SNMP-v3, RADIUS and TACACS+ are supported.

Device Support

Fabric (F), Public Loop (FL), and Translative Loop (TL) are fully supported.

Inter-VSAN Routing (IVR)

Fully supported in SAN-OS Release 1.3(4a) and later with all interop modes.


Legacy Switch Interoperability Modes (2 and 3)

Starting in MDS SAN-OS Release 1.2(1) and continuing in Release 1.3(2a), two legacy switch interoperability modes were introduced:

Interop Mode 2—Introduced in MDS SAN-OS Release 1.2(1), legacy switch interoperability mode 2 allows an MDS VSAN to communicate seamlessly with a Brocade 2100, 2400, 2800 or 3800 series switch without having to modify the configuration of the Brocade switch. "MDS 9000 Legacy Switch Interop Mode 2," provides additional information and a tutorial using this mode.

Interop Mode 3—Introduced in MDS SAN-OS Release 1.3(2a), legacy switch interoperability mode 3 allows an MDS VSAN to communicate seamlessly with a Brocade 3900 or 12000 model switch without having to take the Brocade switch offline. "MDS 9000 Legacy Switch Interop Mode 3,"provides additional information about this mode.

When a VSAN is configured for one of the legacy switch interoperability modes, the Cisco MDS 9000 Family of switches is limited in the following areas when interoperating with Brocade switches:

Legacy switch interop modes only affect the specified VSAN. The MDS 9000 switch can still operate with full functionality in other non-interop mode VSANs. All switches that partake in the interoperable VSAN should have that VSAN set to Legacy Switch Interop, even if they do not have any end devices.

TE ports and PortChannels cannot be used to connect an MDS 9000 switch to non-MDS switches. Only E ports can be used to connect an MDS 9000 switch to a non-MDS switch. However, TE ports and PortChannels can still be used to connect an MDS 9000 switch to other MDS 9000 switches, even when in interop mode.

The active zone set and full zone databases are distributed to other switches.

In MDS SAN-OS Release 1.3(x), Fibre Channel timers can be set on a per VSAN basis. Modifying times, however, requires the VSAN to be suspended. Prior to Release 1.3, modifying timers required all VSANs across the switch to be put into the suspended state.

If new zones are added and the cfgsave command is issued on the Brocade switch, vendor specific frames are sent to the other switches in the fabric. The MDS 9000 switch parses these frames and modifies the full database accordingly. However, the MDS 9000 switch does not save the full database to nonvolatile memory unless the copy running startup command is issued. Using the MDS zoneset distribute vsan # command causes the MDS 9000 switch to emulate the Brocade cfgsave behavior by instructing other switches to save their configuration. The MDS 9000 switch will not save its own configuration unless a copy running-configuration startup-configuration is issued. When a zone set is activated by the MDS 9000 switch, it implicitly sends a cfgsave command to the Brocade switches.

The MDS 9000 switch continues to support the following zoning limits per switch across all VSANs:

2000 zones (8000 in SANOS 3.0)

2000 aliases

1000 zone sets

20000 members

8000 LUN members

256 LUN members per zone/alias


Note Before configuring this number of zones in a multi-vendor environment, determine the maximum number that can be supported by the other vendors present in the environment.


Table 2-2 provides a summary of features and behaviors in legacy switch interop mode for an MDS 9000 switch.

Table 2-2 Summary of Features in Legacy Switch Interop Mode for an MDS 9000 Switch 

Feature
Requirement / Behavior

Minimum MDS SAN-OS Release

1.2(1) for legacy switch interop mode 2; 1.3(2a) for legacy switch interop mode 3.

VSANs

Only the VSANs explicitly set for interop mode are affected. All others maintain their independence.

High Availability

Fully redundant dual supervisor modules maintain full functionality.

PortChannels and TE Ports

They can still be used to directly connect two MDS 9000 switches together, even while in interop mode. However, they cannot be used to directly connect to a non-MDS switch. Standard E ports are required to connect to non-MDS switches.

Zone and Zone Sets

Only the active zone set is propagated. Up to 2000 zones can be supported by the MDS 9000 switch.

Fabric Manager and Device Manager

They can still be used to fully manage the MDS 9000 switch, and to create zones to be distributed to the non-MDS platforms. Fabric Manager can still view the entire mixed topology.

Security

SSH, Telnet, SNMP-v3 and RADIUS are supported.

Device Support

Fabric (F), Public Loop (FL), and Translative Loop (TL) are fully supported.

Inter-VSAN Routing

Fully supported in SAN-OS Release 1.3(4a) and higher with all interop modes.


Legacy Switch Interoperability Mode 4

In Cisco MDS SAN-OS Release 3.0(1), legacy switch interoperability mode 4 was introduced to enable seamless integration with McData switches that are running in McData Fabric 1.0 mode. "MDS 9000 Legacy Switch Interop Mode 4" provides additional information about this mode.

When a VSAN is configured for interoperability mode 4, the Cisco MDS 9000 Family of switches is limited in the following areas when interoperating with McData switches:

Legacy switch interop modes only affect the specified VSAN. The MDS 9000 switch can still operate with full functionality in other non-interop mode VSANs. All switches that partake in the interoperable VSAN should have that VSAN set to legacy switch interop mode 4, even if they do not have any end devices.

TE ports and PortChannels cannot be used to connect an MDS 9000 switch to non-MDS switches. Only E ports can be used to connect an MDS 9000 switch to a non-MDS switch. However, TE ports and PortChannels can still be used to connect an MDS 9000 switch to other MDS 9000 switches, even when in interop mode, and TE ports and PortChannels can carry interop mode 4 VSANs.

Only the active zone set is distributed to other switches.

In MDS SAN-OS Release 1.3(x), Fibre Channel timers can be set on a per VSAN basis. Modifying timers, however, requires the VSAN to be suspended. Prior to Release 1.3, modifying timers required all VSANs across the switch to be put into the suspended state.

The MDS 9000 switch continues to support the following zoning limits per switch across all VSANs:

2000 zones (8000 in SANOS 3.0)

20000 aliases

1000 zone sets

20000 members

8000 LUN members

256 LUN members per zone/alias


Note Before configuring this number of zones in a multi-vendor environment, determine the maximum number that can be supported by the other vendors present in the environment.


Table 2-2 provides a summary of features and behaviors in legacy switch interop mode for an MDS 9000 switch.

Table 2-3 Summary of Features in Legacy Switch Interop Mode 4 for an MDS 9000 Switch 

Feature
Requirement / Behavior

Minimum MDS SAN-OS Release

SAN OS 3.0(1)

VSANs

Only the VSANs explicitly set for interop mode 4 is affected. All others maintain their independence.

High Availability

Fully redundant dual supervisor modules maintain full functionality.

PortChannels and TE Ports

They can still be used to directly connect two MDS 9000 switches together, even while in interop mode. However, they cannot be used to directly connect to a non-MDS switch. Standard E ports are required to connect to non-MDS switches.

Zone and Zone Sets

Only the active zone set is propagated. Up to 2000 zones (8000 in MDS SAN-OS Release 3.0) can be supported by the MDS 9000 switch.

Fabric Manager and Device Manager

They can still be used to fully manage the MDS 9000 switch, and to create zones to be distributed to the non-MDS platforms. Fabric Manager can still view the entire mixed topology.

Security

SSH, Telnet, SNMP-v3 and RADIUS are supported.

Device Support

Fabric (F), Public Loop (FL), and Translative Loop (TL) are fully supported.

Inter-VSAN Routing

Fully supported in MDS SAN-OS Release 1.3(4a) and higher with all interop modes.


Inter-VSAN Routing (IVR)

Inter-VSAN routing (IVR) allows a device that is in one VSAN to communicate with a device that is located in another VSAN. IVR was introduced in MDS SAN-OS Release 1.3(2a).

MDS SAN-OS Release 1.3(4a) introduced IVR for all interop modes within a configuration, so that inter-VSAN routing is now possible between all interop mode VSANs.

See "Interoperability with Inter-VSAN Routing," for more information on IVR and interoperability.

McData Switches


Note Prior to performing an installation, see "McData Switches" in "Caveats," for the latest issues with McData switch interoperability.


When configured for interoperability mode (Open Fabric 1.0), McData switches have the following restrictions and limitations:

Interoperability mode is switch-wide.

Enabling interoperability mode is a disruptive process to the entire switch.

Zoning is restricted to pWWN, and port number zoning is not allowed.

The default zone behavior changes to deny (devices that are not explicitly in a zone are isolated from all other devices).

Domain IDs are restricted to the 97 to 127 range. However, when configuring domain IDs on the McData switch, a range of 1-31 is specified. McData uses an offset of 96 between the configured domain ID and what is actually distributed in the fabric (on the wire).

Fabric Config Server (FCS) is not supported.

When configured for McData Fabric 1.0, in conjunction with an MDS interop mode 4 VSAN (see "MDS 9000 Legacy Switch Interop Mode 4"), McData switches have the following restrictions and limitations:

McData Fabric 1.0 is configured switch wide, and all McData switches must be configured in the same mode.

FC IDs are restricted to the 97 to 127 range. However, when configuring domain IDs on the McData switch, a range of 1-31 is specified. McData uses an offset of 96 between the configured domain ID and what is actually distributed in the fabric (on the wire).

McData SANtegrity features are not supported with an MDS switch in interop mode 4.

Brocade Switches


Note Prior to performing an installation, see "Brocade Switches" in "Caveats," for the latest issues with Brocade interoperability.


When interoperability mode is set, the Brocade switch has the following limitations:

All Brocade switches should be in Fabric OS 2.4 or later.

Interop mode affects the entire switch. All switches in the fabric must have interop mode enabled.

Msplmgmtdeactivate must be run prior to connecting the Brocade switch to either an MDS 9000 switch or a McData switch. This command uses Brocade proprietary frames to exchange platform information. The MDS 9000 switch and McData switches do not understand these proprietary frames, and rejection of these frames causes the common E ports to become isolated.

Enabling interoperability mode is a disruptive process to the entire switch. It requires the switch to be rebooted.

If there are no zones defined in the effective configuration, the default behavior of the fabric is to allow no traffic to flow. If a device is not in a zone, it is isolated from other devices.

Zoning can only be done with pWWNs. You cannot zone by port numbers or nWWNs.

To manage the fabric from a Brocade switch, all Brocade switches must be interconnected. This interconnection facilitates the forwarding of the inactive zone configuration.

Domain IDs are restricted to the 97 to 127 range to accommodate McData's nominal restriction to this same range.

Brocade WebTools will show a McData switch or an MDS 9000 switch as an anonymous switch. Only a zoning configuration of the McData switch or the MDS 9000 switch is possible.

Private loop targets will automatically be registered in the fabric using translative mode.

Fabric watch is restricted to Brocade switches only.

The full zone set (configuration) is distributed to all switches in the fabric. However, the full zone set is distributed in a proprietary format, which only Brocade switches accept. Other vendors reject these frames, and accept only the active zone set (configuration).

The following services are not supported:

The Alias Server

Secure Fabric OS

Management Server

The following services are disabled:

Virtual Channels

Quickloop

QuickLoop Fabric Assist zones

The following services are not valid:

Broadcast zones

Domain/port representation in zones

Trunking

Figure 2-1 displays the features and functionality that are maintained or disabled in a sample MDS 9000 switch to Brocade fabric.

Figure 2-1 Sample Topology with Interop Mode Features