C H A P T E R  6

The System Chassis's Integrated Switch

This chapter contains the following sections:

6.1 Switch Firmware Issues

The following known problems apply to the current release of the switch firmware for this product:

This should not happen during normal operation. The problem was observed when a user sent a sequence of lengthy commands (for example, commands adding many VLANs to a port) to the switch without waiting for the prompt between each command. This filled the switch's input buffer and blocked the status poll messages.

To avoid the problem, always wait for one command to complete before issuing another command on the CLI. If you are using scripts this is especially important.

To do this, type the following:

Console(config)#vlan database
Console(config)#no vlan vlanid

where vlanid is the number identifying a VLAN that you want to remove from the switch's database. Firmware that fixes this problem is now available from http://sunsolve.sun.com (patch number: 114783-xx).

To change the initial spanning tree mode from the default (RSTP) to STP with spanning tree disabled, type:

Console(config)#spanning-tree mode rstp
Console(config)#no spanning-tree

6.2 Issues Affecting the Web Graphical User Interface to the Switch

A graphical user interface (GUI) is available for configuring the switch. To access it, point a web browser at the host name or IP address you have used for the switch.

The following problems have been observed during testing of the web GUI. Sun bug numbers are included where these are available.

then VLANs that have been learned dynamically are not dropped even after the GVRP leave-all timer has expired (normally 10 seconds). These VLANS remain active on the ports that learned them, and you must remove them manually. The following sample command removes the dynamically learned VLAN called vlan 3 from NETP4:

Console#show vlan
VLAN Type    Name             Status    Ports/Channel groups
---- ------- ---------------- --------- -----------------------
1  Static    DefaultVlan      Active     SNP0    SNP1    SNP2 
                                         SNP3    SNP4    SNP5
                                         SNP6    SNP7    SNP8
                                         SNP9    SNP10   SNP11
                                         SNP12   SNP13   SNP14
                                         NETP0   NETP1   NETP2
                                         NETP3   NETP4   NETP5
                                         NETP6   NETP7
2  Static    MgtVlan          Active     NETMGT
3  Dynamic                    Active     NETP4
Console(config)#interface ether NETP4
Console(config-if)#switchport allowed vlan remove 3
Console(config)#vlan database
Console(config-vlan)#no vlan 3

6.3 The Term "Trunk" Meaning Either an Aggregated Link Or a Tagged VLAN Connection

There is confusion in the networking industry over the term "trunking" because it is used to refer both to link aggregation and to tagged VLAN connections between two switches. In the first of these senses it means a redundant high-bandwidth path between two switches. In the second it means a network connection on a LAN segment that is populated only with VLAN-aware devices.

6.3.1 Aggregated Links

You may have encountered the term "trunking" in the sense of link aggregation if you have used the Sun Trunking 1.2.1 product.

Ports can be statically grouped into an aggregate link to increase the bandwidth of a network connection or to ensure fault recovery. Alternatively, you can use the Link Aggregation Control Protocol (LACP) which automatically negotiates an aggregated link between the switch and another network device. For static aggregated links, the switches must be of the same type. For dynamic aggregated links, the switches simply have to comply with LACP. The switch in the blade system chassis supports up to six aggregated links. An aggregated link consisting of two 1000 Mbps ports can support an aggregate bandwidth of 4 Gbps when operating at full duplex.

To implement a configuration combining the ports NETP0 and NETP1 into an aggregated link called channel group 1, you would type the following commands:

Console(config)#interface port-channel 1
Console(config)#interface ethernet NETP0
Console(config-if)#channel-group 1
Console(config)#interface ethernet NETP1
Console(config-if)#channel-group 1

6.3.2 Switch-to-switch Tagged VLAN Trunk Connections

The Sun Fire B1600 Blade System Chassis Switch Administration Guide also uses the term "trunking" in the sense of a point-to-point tagged VLAN connection between two switches. Section 4.3.12 tells you how to configure the chassis's end of a connection like this to an external switch, and section tells you how to use the "switchport mode" command to specify that the connection is a "trunk" (as opposed to a "hybrid") connection. If you specify "trunk" the port transmits and receives tagged frames only - in other words, it sends and receives only frames that identify their source VLAN. (However, note that it sends frames belonging to its default VLAN untagged.) If you specify "hybrid" the port will transmit and receive tagged and untagged frames.

To set the configuration mode for port SNP3, and then to set the switchport mode to trunk for VLANs 12 and 22, you would type the following commands:

Console(config)#interface ethernet SNP3
Console(config-if)#switchport allowed vlan add 12 tagged
Console(config-if)#switchport allowed vlan add 22
Console(config-if)#switchport native vlan 22
Console(config-if)#switchport allowed vlan remove 1
Console(config-if)#switchport ingress-filtering
Console(config-if)#switchport mode trunk
Console(config-if)#switchport acceptable-frame-types tagged

6.4 Setting up a Tagged VLAN Trunk With Cisco Switches

There is a known problem with setting a switch port to trunk mode if that port is connected to a port on a Cisco switch also in trunk mode (note that we use the word "trunk" in the sense of a point-to-point link, not in the sense of an aggregated link). This is because of a standardization issue (Cisco comply with the Cisco standard whereas the switch in the blade system chassis complies with the IEEE 802.1Q standard). It means that it will drop frames from the Cisco switch port's native VLAN.

To work around this problem, you need to configure the system chassis's switch port to hybrid (not trunk) mode, make sure that it has the same native VLAN Id as the Cisco switch, and also make sure that all the VLANs requiring connection to the Cisco switch have been added to the port. You must also stop packets for VLANs that the port is not a member of from entering the port.

Commands for a sample workaround are printed below. These assume a system chassis port (NETP0) with VLAN 1 as its native VLAN and hybrid as its link mode (this is the factory default configuration for the system chassis's network ports).

The commands for the sample workaround also assume a Cisco switch port with trunk as itslink mode, VLAN 10 as its native VLAN, and additional membership of VLANs 11 and 12.

The commands for the workaround in this scenario are:

Console(config)#interface ethernet NETP0
Console(config-if)#switchport allowed vlan add 10
Console(config-if)#switchport native vlan 10
Console(config-if)#switchport allowed vlan remove 1
Console(config-if)#switchport allowed vlan add 11 tagged
Console(config-if)#switchport allowed vlan add 12 tagged
Console(config-if)#switchport ingress-filtering