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Port mirroring
Port mirroring copies the packets passing through a port to the destination port that connects to a
data monitoring device for packet analysis. The copies are called mirrored packets.
Port mirroring includes the following terms:
•
Source
port
—Monitored port on the device. Packets of the monitored port will be copied and
sent to the destination port.
•
Source
device
—Device where a source port resides.
•
Destination
port
—Port that connects to the data monitoring device. Packets of the source port
will be copied and sent to the destination port.
•
Destination
device
—Device where the destination port resides.
•
Mirroring
group
—Includes local mirroring group and remote mirroring group.
{
Local mirroring group
—The source port and the destination port are on the same device.
A local mirroring group is a mirroring group that contains the source ports and the
destination port on the same device.
{
Remote port mirroring
—The source port and the destination port are on different devices.
A remote source group is a mirroring group that contains the source ports. A remote
destination group is a mirroring group that contains the destination port. In remote port
mirroring, mirrored packets are transmitted by the remote probe VLAN from the source
device to the destination device.
Static routing
Static routes are manually configured. If a network's topology is simple, you only need to configure
static routes for the network to work correctly.
Static routes cannot adapt to network topology changes. If a fault or a topological change occurs in
the network, the network administrator must modify the static routes manually.
A default route is used to forward packets that do not match any specific routing entry in the routing
table. You can configure a default IPv4 route with destination address 0.0.0.0/0 and configure a
default IPv6 route with destination address ::/0.
Policy-based routing
Policy-based routing (PBR) uses user-defined policies to route packets. A policy can specify next
hops for packets that match specific criteria such as ACLs.
Policy
A policy includes match criteria and actions to be taken on the matching packets. A policy can have
one or multiple nodes as follows:
•
Each node is identified by a node number. A smaller node number has a higher priority.
•
A node contains the following elements:
{
Match criterion
—Uses an ACL to match packets.
{
Action
—Sets a next hop for the permitted packets. You can associate a next hop with a
track entry, and specify whether the next hop is directly connected.
•
A node has a match mode of
permit
or
deny
.
