Configuring VLANs

Table Of Contents

Configuring VLANs

Configuring Client-Side VLANs

Configuring Server-Side VLANs

Configuring VLANs

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This chapter describes how to configure VLANs on the CSM-S and contains these sections:

•Configuring Client-Side VLANs

•Configuring Server-Side VLANs

To configure VLANs on the SSL daughter card, see the "Configuring VLANs on the SSL Daughter Card" section.

When you install the CSM-S in a Catalyst 6500 series switch, you need to configure the client-side and server-side VLANs. (See Figure 4-1.)

Client-side or a server-side VLAN terminology logically distinguishes the VLANs facing the client-side and the VLANs connecting to the servers or destination devices. However, the CSM-S client and server VLANs function very similarly. For example, new connections can be received on a server VLAN and then be load-balanced to a client VLAN.

The differences between the client-side and server-side VLANs are as follows:

•When configuring bridge mode, you cannot bridge two server VLANs or two client VLANs. You can only bridge a client and a server VLAN.

•Denial of service (DoS) protection features are more aggressive on the client-side VLANs, especially when rate limiting control traffic is sent to the central processing unit.

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Note You must configure VLANs on the Catalyst 6500 series switch before you configure VLANs for the CSM-S. The VLAN IDs must be the same for the switch and the module.

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Figure 4-1 Configuring VLANs

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Note The numbers in Figure 4-1 correspond to the numbers in the following operation.

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1. The CSM-S does not perform a Layer 3 lookup to forward traffic; the CSM-S cannot respond to ICMP redirects.

2. You can configure up to 7 gateways per VLAN for up to 511 client and server VLANs and up to 224 gateways for the entire system. If an HSRP gateway is configured, the CSM-S uses 3 of the 224 gateway entries because traffic can come from the virtual and physical MAC addresses of the HSRP group. The fault-tolerant VLAN does not use an IP interface, so it does not apply toward the 512 VLAN limit.

Configuring Client-Side VLANs

To configure the client-side VLANs, perform this task:

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Caution You cannot use VLAN 1 as a client-side or server-side VLAN for the CSM-S.

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	Command	Purpose
Step 1	Router(config-module-csm)# vlan vlanid client	Configures the client-side VLANs and enters the client VLAN mode1 .
Step 2	Router(config-slb-vlan-client)# ip ip-address netmask	Configures an IP address to the CSM-S used by probes and ARP requests on this particular VLAN2 .
Step 3	Router(config-slb-vlan-client)# gateway ip-address	Configures the gateway IP address.

1 Enter the exit command to leave a mode or submode. Enter the end command to return to the menu's-top level. 2 The no form of this command restores the defaults.

This example shows how to configure the CSM-S for the client-side VLANs:

Router(config-module-csm)# vlan 130 client

Router(config-slb-vlan-client)# ip addr 123.44.50.6 255.255.255.0

Router(config-slb-vlan-client)# gateway 123.44.50.1

Router(config-slb-vlan-client)# exit

Router# show module csm vlan 1

Configuring Server-Side VLANs

To configure the server-side VLANs, perform this task:

	Command	Purpose
Step 1	Router(config-module-csm)# vlan vlanid server	Configures the server-side VLANs and enters the server VLAN mode1 .
Step 2	Router(config-slb-vlan-server)# ip ip-address netmask	Configures an IP address for the server VLAN2 .
Step 3	Router(config-slb-vlan-server)# alias ip-address netmask	(Optional) Configures multiple IP addresses to the CSM-S as alternate gateways for the real server3 .
Step 4	Router(config-slb-vlan-server)# route ip-address netmask gateway gw-ip-address	Configures a static route to reach the real servers if they are more than one Layer 3 hop away from the CSM-S.
Step 5	Router # show module csm slot vlan [client | server | ft] [id vlan-id] [detail]	Displays the client-side and server-side VLAN configurations.

1 Enter the exit command to leave a mode or submode. Enter the end command to return to the menu's-top level. 2 The no form of this command restores the defaults. 3 The alias is required in the redundant configuration. See "Configuring Redundancy."

This example shows how to configure the CSM-S for the server-side VLANs:

Router(config-module-csm)# vlan 150 server

Router(config-slb-vlan-server)# ip addr 123.46.50.6 255.255.255.0

Router(config-slb-vlan-server)# alias 123.60.7.6 255.255.255.0

Router(config-slb-vlan-server)# route 123.50.0.0 255.255.0.0 gateway 123.44.50.1

Router(config-slb-vlan-server)# exit