User`s guide

98 XgOS User’s Guide • September 2014
Mirroring to Port
When you mirror to an output port, the traffic is copied to another physical port that
is on the same I/O Module. Typically, the output port is then connected to a physical
device, like a sniffer. However, this is not a requirement.
The mirrored traffic is copied to the physical port regardless of whether the port has
a physical connection or not. When mirroring to a physical port, there is no
dependency on matching configurations between the Oracle Fabric Interconnect port
and the peer device attached to the port.
Note – Mirroring between input I/O and an output I/O port is not supported
because the input is always a vNIC. The option to mirror to a port only valid for an
output.
Because multiple vNICs can be terminated on a port, the Oracle Fabric Interconnect
supports mirroring all vNICs that are terminated on a port. By supporting this
“mirror all vNICs” functionality, you do not need to individually configure multiple
vNICs for mirroring. Instead, you can mirror all vNICs on a port by issuing one
command on the port. Any vNICs terminated on that port are then mirrored.
Mirroring Considerations
Note – Because mirrors create a duplicate traffic stream, it is possible to
inadvertently cause loops in the network if the mirrors are not created carefully.
Be aware of the following considerations when creating mirrors:
■ Because incorrectly configured mirrors can cause network loops, if you have any
uncertainty about whether your mirrors will cause loops, Oracle recommends
that you contact Oracle Customer Support and request assistance. For
information, see “Support and Accessibility” on page xxvi.
■ As a general rule, only mirror to a port that is connected to a network analyzer.
■ Do not mirror to a vNIC that is not terminated. If the mirror vNIC is not
terminated, the Oracle Fabric Interconnect displays a “resource mismatch” error
message. If you do not terminate the vNIC, the traffic will be copied, but will not
be sent on the vNIC.
■ When mirroring to the same port (for example, on the 10GE module which has
only one port), you should use the optional -mirror-mac=<mac-address>
argument to target a specific hardware address as the destination for the mirrored
packets.