Brocade Communications Systems ICX 7250 series, Руководство по настройке

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Syntax: ip route ip-addr / mask-bits null0 [ metric ] [ distance num ]
To display the maximum value for your device, enter the show default values command. The maximum number of static IP routes the
system can hold is listed in the ip-static-route row in the System Parameters section of the display. To change the maximum value, use
the
system-max ip-static-route command at the global CONFIG level.
The ip-addr variable specifies the network or host address. The Layer 3 switch will drop packets that contain this address in the
destination field instead of forwarding them.
The ip-mask variable specifies the network mask. Ones are significant bits and zeros allow any value. For example, the mask
255.255.255.0 matches on all hosts within the Class C subnet address specified by ip-addr . Alternatively, you can specify the number
of bits in the network mask. For example, you can enter 10.157.22.0/24 instead of 10.157.22.0 255.255.255.0.
The null0 variable indicates that this is a null route. You must specify this parameter to make this a null route.
The metric variable adds a cost to the route. You can specify from 1 through 16. The default is 1.
The distance num variable configures the administrative distance for the route. You can specify a value from 1 through 255. The default
is 1. The value 255 makes the route unusable.
NOTE
The last two variables are optional and do not affect the null route, unless you configure the administrative distance to be 255. In
this case, the route is not used and the traffic might be forwarded instead of dropped.
Configuring load balancing and redundancy using multiple static routes to
the same destination
You can configure multiple static IP routes to the same destination, for the following benefits:
• IP load sharing - If you configure more than one static route to the same destination, and the routes have different next-hop
gateways but have the same metrics, the Layer 3 switch load balances among the routes using basic round-robin. For example,
if you configure two static routes with the same metrics but to different gateways, the Layer 3 switch alternates between the two
routes.
• Backup Routes - If you configure multiple static IP routes to the same destination, but give the routes different next-hop
gateways and different metrics, the Layer 3 switch will always use the route with the lowest metric. If this route becomes
unavailable, the Layer 3 switch will fail over to the static route with the next-lowest metric, and so on.
NOTE
You also can bias the Layer 3 switch to select one of the routes by configuring them with different administrative distances.
However, make sure you do not give a static route a higher administrative distance than other types of routes, unless you want
those other types to be preferred over the static route.
The steps for configuring the static routes are the same as described in the previous section. The following sections provide examples.
To configure multiple static IP routes, enter commands such as the following.
device(config)# ip route 10.128.2.69 255.255.255.0 10.157.22.1
device(config)# ip route 10.128.2.69 255.255.255.0 10.111.10.1
The commands in the previous example configure two static IP routes. The routes go to different next-hop gateways but have the same
metrics. These commands use the default metric value (1), so the metric is not specified. These static routes are used for load sharing
among the next-hop gateways.
Static routes configuration
Brocade FastIron Layer 3 Routing Configuration Guide
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