Hitachi 3100, Network Administration Manual

Page: 27 / 89

Default gateways
The server supports multiple default gateways for routing IP traffic. When
connected to multiple IP networks, add a default gateway for each network to
which the server is connected. This configuration allows the server to direct
traffic through the appropriate default gateway by matching source IP
addresses specified in outgoing packets with the gateway on the same
subnet.
With multiple default gateways, the server routes IP traffic logically, reducing
the need to specify static routes for every network that connects with a
particular server.
Static routes
Static routing provides a fixed path for data in a network. When a server on a
network is connected to additional networks through a router, communication
between that server and the remote networks can be enabled by specifying a
static route to each network.
Static routes are set up in a routing table. Each entry in the table consists of
a destination network address, a gateway address, and a subnet mask.
Entries for static routes in the server’s routing table are persistent, meaning
that, if a server is restarted, the route table preserves the static routing
entries.
The NAS server supports gateway, network and host static routes. The
Default
option sets up a gateway and does not require a destination. Select
the
Network
option to set up a route to address all of the computers on a
specific network. Select the
Host
option to address a specific computer on a
different network. The maximum possible number of static routes is 127
(default gateways also count against this total).
In most cases, for IPv6, it is not necessary to statically configure gateways as
they are automatically discovered through the received router
advertisements.
Dynamic routes
The NAS server supports ICMP redirects and RIP versions 1 and 2 , which
enable it to dynamically add routes to its route table.
ICMP redirects
Routing overview 27
Hitachi NAS Platform Network Administration Guide