Questions tagged [dot1q]
For questions about IEEE 802.1Q also referred to as Dot1q, which is the networking standard that supports virtual LANs (VLANs) on an IEEE 802.3 Ethernet network. For instance, you are setting up two switches and want to use trunk between them, but do not know how.
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dot1q L3 router sub-interfaces and L2 switch ports
I have a router with multiple L3 sub-interfaces. On the other side I have a L3 switch (Nexus 9K) that I'd like to have multiple hosts that are on the switch route their traffic to one of the router ...
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Q-in-Q on QFX5120
I'm building dot1Q tunneling between 2 Cisco routers and when I used only 1 QFX switch it all works fine.
However when I try to use 2 QFX switches with basically the same configuration I cannot get ...
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3
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dynamic mac address added all hosts through the Do1Q tunnel
we have a nexus switch, we configure two customer ports in different switches with (mode Dot1Q tunnel)
as all traffic must have two VLAN tags, an inner tag, and an outer tag,
in our network, we ...
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Port only in trunk mode vs encapsulating the frame
A network with 2 switches, each switch has 2 vlan, one called vlan 10 and another vlan 20.
A port-channel with 2 uplinks (trunk). Why in a layer 2 scenario I don't need to configure the trunks with ...
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Private VLANs Same As VLANs!
The common VLANs provides a layer 2 speration flooding and broadcasting is limited to each virtual lans.
Im wondering what is the purpose of the private VLANs also the secondary VLANs (isolated and ...
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difference between switchport trunk encapsulation dot1q and switchport mode trunk
I am new to network engineering and I am currently delving deep into L2 functionality.what is the difference between these two commands:
1 switchport trunk encapsulation dot1q
2 switchport mode trunk
...
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2
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Capturing dot1q packets with Wireshark on a PC
I have spent the last few hours trying to capture some trunk packets so I can see and examine the dot1q VLAN field. I have tried mirroring the trunk port to my PC using the following commands on Cisco ...
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MTU size for PPPOE with QinQ
i used at as A pppoe server
i have used QINQ secend tag in rotuer
interface TenGigabitEthernet2/0/0.904
description Cust1-QINQ
encapsulation dot1Q 904 second-dot1q any
pppoe enable group PPPOE-...
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Q-IN-Q Tunnel between cisco and mikrotik not work
i have try to make A Q-IN-Q tennel between two router (cisco and Microik) through cisco switch
in mikrotik
VLAN ID = 10 IN interface ether1
VLAN ID = 20 in interaface Vlan10
ip address in interface ...
- 331
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Cannot create connection between two routers in same VLAN via switch
I currently have a Cisco 2960-24TT switch (switch1) and a Cisco 1841 router (router1) that form part of my core network connecting other VLANs and devices. The two ports on router1 have been ...
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L2 / L3 on CISCO ASR
I am new to CISCO and have the following problem:
I have 3 routers. Between these only one physical connection.
The VLAN 100 is connected to R1 and R2.
The VLAN 200 is connected to R1, R2 and R3.
The ...
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1
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1k
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Layer 3 switch model 3950 encapsulation
How to ensure trunk link in the switch are using dot1q encapsulation, when dtp (dynamic trunking protocol) is enable along with vtp.
I know when manually setting trunk links, you can force the trunk ...
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1
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Dot1q tags, sub-interfaces
Please consider dot1q frames tagged 100 circulating on a LAN (VLAN 100).
To go out onto the Internet, frames have to go through a PPPoE sub-interface which is configured as below:
interface ...
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1
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681
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Juniper EX4600: multicast not working in vlan default. [closed]
I have a Juniper EX4600 switch which I'm using for host connectivity (obviously). Now I need to set up a VRRP/CARP between two hosts that are in the same vlan, and it's the default one. Surprisingly, ...
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Bridge traffic forwarding in vlans
on a trunk, switch A having, say vlan 10 allowed and the other switch B does not. Switch B doesn't even know about that vlan.
How does switch A behave in forwarding broadcasts in vlan 10? Will frames ...
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Cisco QinQ - More than one provider vlan (s-vlan) on dot1q-tunnel port
When we configure a qinq tunneling, the port, which performs the encapsulation, has the next command-lines:
interface g0/10
switchport
switchport mode dot1q-tunnel
switchport access vlan xxx &...
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1
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Respect VLAN through routers with DHCP server on WAN
I would like to create a network like the one in the screenshot. I would have 2 VLANs :
-VLAN10 : Service1
-VLAN20 : Service2
Routing is working but i don't know if I can have adresses on 192.168.1....
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0
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Juniper EX3300 and Q-in-Q
I have a Juniper EX3300 switch that has a 10Gbps connection to our upstream provider.
Our upstream provider (lets call them Provider A) passes us various connections on tagged VLANs over this single ...
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Cisco 891: sub-interface VS SVI approach
I have a SOHO environment for which I'm using Cisco 891-K9 as the ISP GW.
But the nature of Cisco 891 is that it's both a router and a switch with 10 ports.
Will switch ports (both access and trunk ...
user10221
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Multiple VLANs on a single port Virtual Host [closed]
I have a physical host server connected to an HP (say, 2650 series?) switch. The host is running multiple Hyper-V virtualized OSes, each on a different VLAN. If I make the switch port dot1q tagged for ...
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Cisco router dot1Q monitoring
How can I monitor on a Cisco router if dot1Q packets arrive on the trunk interface or if others arrive on that interface (like ISL, the old protocol of Cisco)?
How can I do this and what is the best ...
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Dell powerconnect 6248 voice vlan next to dot1x
We are testing currently dot1x auth against FreeRADIUS/AD in the network. The vlans are dynamically assigned by FreeRADIUS on AD-group base. This works, but now the problem comes:
We wanted to add ...
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Accidentally Removed Allowed VLANs from Cisco Switch Dot1Q Trunk
I am adding a new VLAN to an existing trunk port between two Cisco Catalyst switches (3750's). In the process of adding the new VLAN, it appears that I've removed the existing allowed VLANs on the ...
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