Cisco 2960-X and 2960-CX Series switches as L3

[gauravjagtap]

Hello All,

I was wondering if I can configure Cisco 2960-x and CX series switches as L3 for inter vlan routing with LAN Base IOS. And also if I can configure DHCP relay on these vlans?

Thanks

Gaurav

[Mark Malone]

Hi

you can check your specific features are available per license and platform on the feature navigator

http://cfn.cloudapps.cisco.com/ITDIT/CFN/jsp/index.jsp

The X series can do basics routing , and the ip routing command is there for intervlan routing

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/routing/configuration_guide/b_rt_152ex_2960-x_cg/b_rt_152ex_2960-x_cg_chapter_010.html

Configuring IP Unicast Routing

By default, IP routing is disabled on the switch. For detailed IP routing configuration information, see the Cisco IOS IP Configuration Guide, Release 12.2 from the Cisco.com page under Documentation > Cisco IOS Software Releases > 12.2 Mainline > Configuration Guides.

In these procedures, the specified interface must be a switch virtual interface (SVI)-a VLAN interface created by using the interface vlanvlan_id global configuration command and by default a Layer 3 interface. All Layer 3 interfaces on which routing will occur must have IP addresses assigned to them. See the "Assigning IP Addresses to SVIs" section .

Note

The switch supports 16 static routes (including user-configured routes and the default route) and any directly connected routes and default routes for the management interface. You can use the "lanbase-default" SDM template to configure the static routes. The switch can have an IP address assigned to each SVI.

Procedures for configuring routing:

• To support VLAN interfaces, create and configure VLANs on the switch or switch stack, and assign VLAN membership to Layer 2 interfaces. For more information, see chapter: Configuring VLANs.
• Configure Layer 3 interfaces (SVIs).
• Enable IP routing on the switch.
• Assign IP addresses to the Layer 3 interfaces.
• Configure static routes.

Enabling IP Unicast Routing

By default, the switch is in Layer 2 switching mode and IP routing is disabled. To use the Layer 3 capabilities of the switch, you must enable IP routing.

	Command or Action	Purpose
Step 1	configure terminal Example: Switch# configure terminal	Enters global configuration mode.
Step 2	ip routing Example: Switch(config)# ip routing	Enables IP routing.

The XR is probably what you want its the layer 3 version of 29xx

[gauravjagtap]

Thanks Mark. Just now I tested the command and both of the features inter vlan routing and ip helper address work in cisco 2960 with lanlite.

Also can you suggest if I need to alter sdm template in order to support these features without affecting the switch performance as I was using default template.  

Thanks

Gaurav

[Mark Malone]

Hi

You should have something like this to use  ....sdm pre lanbase-routing

[gauravjagtap]

Please find below output from Cisco Switch. Does it suggest lanbase-defaul is better than lanbase-routing?

Switch(config)#sdm prefer ?
  default          Default bias
  lanbase-default  Enhanced support for both IPv4 and IPv6 Routing
  lanbase-routing  Supports both IPv4 and IPv6 Static Routing

Thanks

Gaurav

[Mark Malone]

Yes if you have enhanced use that , my standard 29s don't have that as an option as there used for pure layer 2 access

[gauravjagtap]

Thank you Mark for sorting this out for me.

[Garry Cross]

I have used "ip routing" without changing the template from lanbase-default on a 2960X. If you look at the tables of resources it would seem to me the lanbase-default supports more of everything so why would one choose the lanbase-routing template?

2960X-1#show sdm prefer lanbase-routing
 "lanbase-routing" template:
 The selected template optimizes the resources in
 the switch to support this level of features for
 0 routed interfaces and 255 VLANs.

  number of unicast mac addresses:                  4K
  number of IPv4 IGMP groups + multicast routes:    0.375k
  number of IPv4 unicast routes:                    0.875k
    number of directly-connected IPv4 hosts:        0.875k
    number of indirect IPv4 routes:                 80
  number of IPv6 multicast groups:                  0.25K
  number of IPv6 unicast routes:                    0.875k
    number of directly-connected IPv6 addresses:    0.75K
    number of indirect IPv6 unicast routes:         32
  number of IPv4 policy based routing aces:         0
  number of IPv4/MAC qos aces:                      0.375k
  number of IPv4/MAC security aces:                 0.375k
  number of IPv6 policy based routing aces:         0
  number of IPv6 qos aces:                          0.125k
  number of IPv6 security aces:                     0.25K

2960X-1#show sdm prefer
 The current template is "lanbase-default" template.
 The selected template optimizes the resources in
 the switch to support this level of features for
 0 routed interfaces and 1024 VLANs.

  number of unicast mac addresses:                  16K
  number of IPv4 IGMP groups + multicast routes:    1K
  number of IPv4 unicast routes:                    3K
    number of directly-connected IPv4 hosts:        2K
    number of indirect IPv4 routes:                 1K
  number of IPv6 multicast groups:                  1K
  number of IPv6 unicast routes:                    3K
    number of directly-connected IPv6 addresses:    2K
    number of indirect IPv6 unicast routes:         1K
  number of IPv4 policy based routing aces:         0
  number of IPv4/MAC qos aces:                      0.5K
  number of IPv4/MAC security aces:                 0.625k
  number of IPv6 policy based routing aces:         0
  number of IPv6 qos aces:                          0.5K
  number of IPv6 security aces:                     0.625k