Change Vlan Port Tag And Untagged Settings - Cisco ONS 15454 Troubleshooting Manual

Chapter 1 General Troubleshooting
normal runt packets count at the network device attached to the Untag port. This symptom/limitation also
exists when ports within the same card or ports within the same chassis are put on the same VLAN, with
a mix of tagged and untagged.
Figure 1-32 VLAN with Ethernet Ports at Tagged and Untag
Workstation #1 ONS Node
with Ethernet card
VLAN port set to Tagged
Table 1-25
Table 1-25 Verify VLAN Connection to Network Device from Untag Port
Possible Problem
The Tagged ONS 15454 adds the
IEEE 802.1Q tag and the Untag
ONS 15454 removes the Q-tag without
replacing the bytes. The NIC of the
network device categorizes the packet
as a runt and drops the packet.
Dropped packets can also occur when
ARP attempts to match the IP address
of the network device attached to the
Untag port with the physical MAC
address required by the network access
layer.

Change VLAN Port Tag and Untagged Settings

Step 1 Display the CTC card view for the Ethernet card involved in the problem VLAN.
Step 2 Click the Provisioning > Ether VLAN tabs
November 2004
describes the possible problems and the solution.
1.8.16 VLAN Cannot Connect to Network Device from Untag Port
ONS Node
with Ethernet card
VLAN port set to Untag
SONET/SDH
Ethernet
Solution
The solution is to set both ports in the VLAN to Tagged to
stop the stripping of the 4 bytes from the data packet and
prevent the NIC card in the network access device from
recognizing the packet as a runt and dropping it. Network
devices with IEEE 802.1Q-compliant NIC cards accept the
tagged packets. Network devices with non IEEE 802.1Q
compliant NIC cards still drop these tagged packets. The
solution might require upgrading network devices with
non-IEEE 802.1Q compliant NIC cards to IEEE 802.1Q
compliant NIC cards. You can also set both ports in the
VLAN to Untag, but you will lose IEEE 802.1Q compliance.
(Figure 1-33).
Cisco ONS 15454 Troubleshooting Guide, R4.6
Workstation #2
1-85