Configuring The Default Gateway - Cisco DS-C9216I-K9 Configuration Manual

Chapter 22 Configuring IP Services

Configuring the Default Gateway

The IP address for a switch's default gateway should be configured along with the IP static routing
commands (IP default-network, destination prefix, and destination mask, and next hop address)
If you configure the static route IP forwarding and the default-network details, these IP addresses will
Tip
be used regardless of the default-gateway being enabled or disabled. If these IP address are configured
and not available, the switch will fall back to using the default gateway IP address, if you have configured
it. Be sure to configure IP addresses for all entries in the switch.
When the Ethernet interface is configured, the switch should point to the gateway router for the IP
network. The host accesses the gateway using a gateway switch. This gateway switch is configured as
the default gateway. The other switches in the fabric that are connected to the same VSAN as the gateway
switch can also be connected through the gateway switch. Every interface connected to this VSAN
should be configured with the VSAN IP address of the gateway switch.
Figure 22-2
1.1.1.10
Switch A
Switch D
In Figure
has the IP address 1.12.11.3, and Switch D has the IP address 1.12.11.4. Switch A is the gateway switch
with the Ethernet connection. The NMS uses the IP address 1.1.1.10 to connect to the gateway switch.
Frames forwarded to any switch in the overlaid VSAN 1 are routed through the gateway switch.
Configuring the gateway switch's IP address, 1.12.11.1, in the other switches enable the gateway switch
to forward the frame to the intended destination. Similarly, if a non-gateway switch in the VSAN
forwards a frame to the Ethernet world, the frame is routed through the gateway switch.
When forwarding is disabled (default), IP frames are not sent from one interface to another. In these
cases, the software performs local IP routing between two switches using the in-band option for Fibre
Channel traffic and the mgmt0 option for Ethernet traffic.
When a VSAN is created, a VSAN interface is not created automatically. You need to specifically create
the interface.
OL-7753-01
Overlay VSAN Functionality
NMS
Ethernet connection
1.12.11.1
VSAN 1
1.12.11.1
1.12.11.4
22-2, Switch A has the IP address 1.12.11.1, Switch B has the IP address 1.12.11.2, Switch C
Switch B
1.12.11.2
1.12.11.1
Switch C
1.12.11.1
1.12.11.3
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
Configuring the Default Gateway
22-3