Viavi Apex Enterprise G3-APEX-ENT-32T, Руководство пользователя, Страница: 356 / 380

Troubleshooting common issues
356 GigaStor (23 Feb 2018) — Archive/Non-authoritative version
The Gigabit NIC no longer strips VLAN tags, so the symptom in Observer is
resolved.
VLAN Statistics tool is not working
Symptoms : “No VLAN” is the only VLAN ID that shows up in the VLANs column
in VLAN Statistics. You are not seeing all VLANs you have on the network.
Causes : To display VLAN Statistics, Observer checks each packet for a VLAN
tag; if no tag is present, the packet is logged as “No VLAN.” Both 802.1Q or ISL
VLAN tags are stripped unless the SPAN destination port to which the analyzer is
attached has been configured to include VLAN tags.
Solutions : Configure the switch to retain the VLAN tags through the monitor
port. This may be an option in the Mirror or SPAN command on the switch, or
you may have to configure the port as a trunk prior to defining it as a SPAN port.
Even if the switch is monitoring a trunk or uplink port it may strip VLAN tags
unless you configure that port to retain the tags. Refer to the documentation
from your switch for details on configuring VLANs, trunks, and analyzer ports.
If connecting Observer to a Cisco switch, see the following link (it does require
a TAC account): http://www.cisco.com/en/US/customer/products/hw/switches/
ps708/products_tech_note09186a008015c612.shtml .
If you use a Cisco Catalyst 4500/4000, 5500/5000, or 6500/6000 Series Switch
running CatOS you must configure the destination port as a trunk port prior to
configuring the SPAN port using the set trunk and set span commands:
set trunk
module / port
[on | off | desirable | auto | nonegotiate]
[vlan_range] [isl | dot1q | negotiate]
set span
source_port
destination_port
[rx | tx | both]
For example, to configure module 6, port 2 for monitoring an 802.1Q VLAN setup,
you would enter the following commands:
switch (enable) set trunk 6/2 nonegotiate dot1Q
switch (enable) set span 6/1 6/2
For Cisco Catalyst 2900/3500, 4500/4000 and 5500/5000 Series Switches Running
IOS 12.1 or later, encapsulation forwarding is set as a part of the SPAN command,
which has the following syntax:
monitor session session_number (source | destination)
interface type/num [encapsulation (dot1q | isl)]
To monitor 802.1Q VLAN traffic passing through Fast Ethernet 02 via a SPAN port
set up on Fast Ethernet 0/6, you would enter the following commands:
C4000 (config) # monitor session 1 source interface fastethernet 0/2
C4000 (config) # monitor session 1 destination interface
fastethernet 0/6 encapsulation dot1Q