Cisco Catalyst 2960 Series, Руководство по настройке

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the switch routes traffic from another VLAN to the monitored VLAN, that traffic is not monitored and
not received on the SPAN destination port.
•
STP
—
A destination port does not participate in STP while its SPAN or RSPAN session is active. The
destination port can participate in STP after the SPAN or RSPAN session is disabled. On a source port,
SPAN does not affect the STP status. STP can be active on trunk ports carrying an RSPAN VLAN.
• CDP — A SPAN destination port does not participate in CDP while the SPAN session is active. After
the SPAN session is disabled, the port again participates in CDP.
•
VTP
—
You can use VTP to prune an RSPAN VLAN between switches.
•
VLAN and trunking
—
You can modify VLAN membership or trunk settings for source or destination
ports at any time. However, changes in VLAN membership or trunk settings for a destination port do
not take effect until you remove the SPAN destination configuration. Changes in VLAN membership
or trunk settings for a source port immediately take effect, and the respective SPAN sessions automatically
adjust accordingly.
• EtherChannel — You can configure an EtherChannel group as a source port a SPAN destination port.
When a group is configured as a SPAN source, the entire group is monitored.
If a physical port is added to a monitored EtherChannel group, the new port is added to the SPAN source
port list. If a port is removed from a monitored EtherChannel group, it is automatically removed from
the source port list.
A physical port that belongs to an EtherChannel group can be configured as a SPAN source port and
still be a part of the EtherChannel. In this case, data from the physical port is monitored as it participates
in the EtherChannel. However, if a physical port that belongs to an EtherChannel group is configured
as a SPAN destination, it is removed from the group. After the port is removed from the SPAN session,
it rejoins the EtherChannel group. Ports removed from an EtherChannel group remain members of the
group, but they are in the inactive or suspended state.
If a physical port that belongs to an EtherChannel group is a destination port and the EtherChannel group
is a source, the port is removed from the EtherChannel group and from the list of monitored ports.
• Multicast traffic can be monitored. For egress and ingress port monitoring, only a single unedited packet
is sent to the SPAN destination port. It does not reflect the number of times the multicast packet is sent.
• A private-VLAN port cannot be a SPAN destination port.
• A secure port cannot be a SPAN destination port.
For SPAN sessions, do not enable port security on ports with monitored egress when ingress forwarding
is enabled on the destination port. For RSPAN source sessions, do not enable port security on any ports
with monitored egress.
• An IEEE 802.1x port can be a SPAN source port. You can enable IEEE 802.1x on a port that is a SPAN
destination port; however, IEEE 802.1x is disabled until the port is removed as a SPAN destination.
For SPAN sessions, do not enable IEEE 802.1x on ports with monitored egress when ingress forwarding
is enabled on the destination port. For RSPAN source sessions, do not enable IEEE 802.1x on any ports
that are egress monitored.
SPAN and RSPAN and Device Stacks
Because the stack of switches represents one logical switch, local SPAN source ports and destination ports
can be in different switches in the stack. Therefore, the addition or deletion of switches in the stack can affect
a local SPAN session, as well as an RSPAN source or destination session. An active session can become
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
482
Information About SPAN and RSPAN