Questions tagged [vlan]
For questions about Virtual LANs (VLANs) which are used to divide what otherwise would be a single OSI layer-2 broadcast domain into multiple, logical OSI layer-2 broadcast domains.
1,215
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Intermittent Network Performance Problems
I've been dealing with an intermittent issue in my network for several weeks now.
Symptoms:
Periodic "Destination host unreachable.", and similar errors when pinging. The following is ...
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1
answer
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Why there's no "show vlan" command on my Cisco NCS-5001?
I'm trying to learn my way around Cisco switches by watching an online course [1] and trying the commands from there on a switch I have access to. One of the first commands I've tried, show vlan ...
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2
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135
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Help segmenting/isolate my network with VLANs [closed]
I have a couple of IP cameras (live view and recording via an NVR) and DVR (with analogue cameras) connected by ethernet on my network.
Nothing is separated atm; i.e. everything can access everything ...
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361
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Best practice / advice for cisco 3560 behind Virtualised OPNsense
Currently I run the below scheme. The problem is that when ESXi is down it takes down all the network with it, so I have to boot up another router to log in to it.
WAN > OPNsense (in ESXi)> ...
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When creating a LAG, what VLAN conditions should be satisfied?
There are two interfaces which are to be added in a LAG. The attributes which should be same are speeds and MTU values.
What about physical interfaces which are in different VLANs.
For example,
Port 1 ...
2
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1
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865
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How to capture mixture of packets with and without VLAN tag over LACP with tcpdump?
Given following configuration in Linux:
bond0 in LACP (802.3ad) mode with two VLAN networks running over it.
bond0.111 configured with static IP
bond0.222 configured with DHCP
How to capture packets ...
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1
answer
236
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VLAN Filtering not working
On Cisco devices I'm looking to enable some filtering for one specific vlan (id 110).
Here is my config : (192.33.57.177 is the DHCP server host)
ip access-list extended VLAN110-DHCP
permit ip any ...
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48
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STP configurations
In my design, there will be a few be a few rings of edge switches that are connected to my distribution switch. (alcatel 6860-U28) The distribution switch will then be connected to my core router ( ...
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2
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913
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How to monitor vlan using SNMP?
I am a newbie to building a monitor system using Prometheus and SNMP exporter, I have succeeded get metric from the physical interface, but I want to monitor VLAN on a trunk port, is that possible ? ...
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86
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BPDU Header System ID Extension
Previously network switches was using the 8 byte field Bridge Priority to identify a root on the network.When networks grows and becomes complex vlan creation comes into play the 2 bytes Bridge ...
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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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I cannot Encapsulate on Router
I have VLAN10 and VLAN20, I am trying to communicate between computers with the same VLAN on the following setup:
I want to apply encapsulation from Router but it doesn't seem to recognize ...
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1
answer
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PAT with multiple VLAN
I've set up a network with 4 VLAN, 3 VLAN configured PAT on it and 1 VLAN configured STATIC NAT. The router is acting as the DHCP server. Outside of my router I have another router acting as "the ...
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2
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intervlan routing with PfSense
I Need some guidance on getting my lab networking configured. Any support is appreciated.
My Lab consists of:
2 cisco switches: 2960s(access layer 2) and 3750X(ip routing/layer 3)
Xenserver with ...
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2
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626
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Access printer in VLAN1 from VLAN2
I have a network printer (Brother MFC-L8690CDW) connected to Cisco RV340W (with latest firmware) on VLAN1.
I have installed driver and it works as usual no issues there.
Now we have created VLAN2.
My ...
- 103
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3
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Cisco SG-350 Switch and Fortigate Firewall Configuration
I'm not what you would call a Network Engineer, but right now i have a (somewhat) complex network problem that i have to solve. I must configure a SG-35028p cisco switch and a fortigate 60f firewall ...
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75
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How can i make every network on this topology speak together?
i'm working on this topology for so long and i didn't manage to make every network speak together with different VLAN on each network.
On this topology:
When i trace a packet sent from PC3 to PC4, ...
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1
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324
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Trunking multiple VLANs into a single trunk port on a 3650 Switch
Morning:
I'm new to the world of Cisco Packet tracer, and I am creating a network for a uni project. So far, what I have is:
5 VLANs (subnetted to 192.168.2.0/26, 192.168.3.0/36 etc)
All are ...
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0
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Computer getting Unable to Identify Network UNLESS Vlan is changed [closed]
This is a problem that has long plagued this environment.
At seemingly random times (measured generally in months), a computer may suddenly lose connectivity to the network.
It still is able to send ...
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3
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542
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Site-to-site IPSec tunnel over Load balancer
I'm having a following topology
Could this be achieved? I've configured this network, but routing between the two VLAN-s are not working. Using Ubiquity Edge X routers.
Could this be archived with ...
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2
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429
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Network topology for merging two different layer 2 networks
I have a scenario, (shown in attach diagram)
where i need to merge traffic from two server 1 , 2 to target server 3. All three are on different vlans/subnets.
With layer 3 switch in between would it ...
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937
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Why some situations, PC can connected to trunk port and work fine?
I want to know about tagged and untagged vlan mechanism then I try to configure like this
When I connected PC3 to trunk port on Packet Tracer, It doesn't work and a switch dropped PC3's frame if I ...
2
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1
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171
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Why can my device not get an ip from DHCP in a network with 2 VLANS of which one has DHCP?
In our company we have a CISCO 2811 Switch accompanied by an HP1920 Switch. Our current configuration consists of 2 VLANS:
VLAN-2 that has no DHCP in IP range 192.168.0.0/24
VLAN-5 That contains DHCP ...
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1
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480
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VLAN Device limitations
i was reading about the Vlan and to be more specific the disadvantages of VLAN and the information resource mentioned that Vlan has Device limitations as follows :
Device limitations :
The ...
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2
answers
536
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Can a Core Switch detect a duplicate IPv4 for two computers not directly connected to it?
I have a Core Switch (routing capability) connected to two access switches. Each switch has a computer connected to it with the same IP and same VLAN. The Core Switch operates as a Level 3 device. All ...
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86
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CMTS (DOCSIS 3.0) with CGN (CGNat)
For a new project/building I am working with the CMTS model MA5633-XB10 by Huawei.
The usual way is done by implementing two DHCP servers in the same VLAN, from which the CPE gets the private IP ...
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0
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Using a switch to dynamically connect and disconnect multiple devices together in a point to point configuration
I have an interesting issue. I have to use a switch to dynamically connect and disconnect multiple devices together in a point to point configuration, without changing anything on the end user side.
...
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552
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Tagged frames onto untagged (access) port!
have been trying to understand ingress behaviour on untagged port, specially w.r.t tagged frames. On going through ieee 802.1q doc, i found this (8.6.2) :
"Each Port may support an Enable Ingress ...
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If we already have default VLAN, Why we need Native VLAN? [duplicate]
What is the need of Native VLAN and default VLAN. How they are related?
Can Somebody explain this in detail?
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Sending tagged traffic to untagged port?
What happens when an untagged port receives tagged frames, whether they are dropped or not !?.
Say, A computer is connected to a switch on untagged port (as most would recommend). On it I have used ...
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Is is possible to send traffic from custom vlan to vlan 1?
I have a problem with understanding networking. Can you help me to understand if i'm right or not and what's the best solution, please?
I'm trying to extend L2 network to the cloud and use current ...
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136
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Where are VLAN tagged packets? [duplicate]
Are they only in trunk links between switches/routers' packets?
Is there any way an endpoint sees tagged VLAN packets? (containing VLAN tags) What if I an endpoint sends a tagged packet that ...
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ping in the same VLAN with multiple switches in between
Refreshing VLAN knowledge with PT7.3, I came across some unexpected behavior.
Why does a chain of switches having proper trunk configuration between them DROP packets? Trying to ping hosts from the ...
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why it isnt possible to convert span into rspan by cabling two ports?
On a on a switch that only support span, and dont support rspan, as long as span only allow destination port to be on the same switch as the source, why cant we connect two switch ports together with ...
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3
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675
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IOS. Whats the difference between these 2 commands
I am completing an online course for the network+ and am going through one of the labs. Here is a diagram of the network in question.
Specifically I have a switch with 24 fast ethernet ports and ...
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3
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492
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How to communicate Different VLANs in Different Switches
I have 3 switches, 2 switches connected to 1 main switch.
I have VLAN6, VLAN7, VLAN8 and VLAN9.
VLAN6 has VLAN6-1 end device.
VLAN7 has VLAN7-1 end device.
VLAN8 has VLAN8-1 and VLAN8-2 end devices.
...
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3
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Do i need VLAN per customer when i want to give users (secure) access to specific customer sites
This question is a follow up on this question. We are currently working on the network design, nothing is implemented yet.
Our network will exist out of our own (internal) network and lot of customer ...
- 219
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Vlan Routing with ESXI and L3 Cisco Switch
Please, i need your help. I have read all the posts from the internet, but i don't know what is wrong.
i want to ping from PC10 (portgroup in Vlan 10 with ip 1.1.10.200, GW 1.1.10.2) to the int vlan ...
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2
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342
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When do ACLs on SVIs get applied on Cisco Catalyst devices?
I don't understand exactly when an ACL will get applied when on an SVI. Given the following (pseudo) configuration
int vlan 100
ip address 10.0.0.1 255.255.255.0
ip access-list in in
ip access-...
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3
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63
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Communcation between vlans and router
Can all VLANs be allowed to communicate with a router but not between VLANs?
If it is possible, then how to achieve it?
The VLANs and router are in the same subnet.
I have topology like this:
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990
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Why can't I connect to PfSense via the switch?
Our current firwall is deprecated and we decided to exchange it with an PfSense server.
In my test setup I configured the interfaces as follows:
igb0 = WAN
enabled
igb1 = LAN (should be VLAN trunk ...
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How to enable Inter-VLAN multicast traffic on a layer 3 Siemens RX1510 Network Switch using IGMP?
I have a single Layer 3 Siemens RX1510 network switch split into 4 separate VLANs on different subsets.
Name | Gateway | Subnet
VLAN1 | 198.97.100.123 | 255.255.255.0
VLAN2 |...
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0
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Connecting layer 3 switches together without trunking
I currently have 2x Juniper EX4200 and I'm looking into changing it into Ubiquiti EdgeSwitchs.
The diagram:
SW01 and SW02 are connected to each other using OSPF P2P. Both of the switches have their ...
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WHY and HOW do routers and vlans break broadcast domains?
Everybody says routers (and vlans) break broadcast domains, but nobody goes into WHY that is, it seems.
What's the router logic?
Say I have three routers on my lan, with one main router and the ...
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7
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2k
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IP Helper in Multiple Access Switches
Just a dumb question..
I have 1 core switch and 5 access switches.
Just wondering if it would be best to setup the IP helper on all access switches rather than just on the core switch?
Does this ...
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2
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557
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VLANS - Layer 2 vs Layer 3 Juniper & Netgate/PfSense
I am working on setting up VLANS on a basically default switch configuration for my SMB network. They have 5 juniper ex2200 switches that are all on the same subnet and have only a default vlan. I ...
3
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1
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284
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cisco switchport trunk native vlan
we have switch catalyst 3850 and we need to enable the PXE boot on a port configured in trunk with configured three VLAN (4040, 4050 and 4060). To permit the PXE boot and deploy to work we set on the ...
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418
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Cisco router on a stick with public ip wan (ISP)gateway
I am trying to create a router on a stick with an outside facing sub-interface with a public IP from an ISP. I have tried to configure NAT and routing but I just cant get to ping the internet. I'm ...
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256
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How do (LANCOM) Tag-Based vlan groups work and on which vlan does the device respond?
I just started a new job and part of it is to manage and maintain the ICT. As the previous network/system engineer left the company i'm on my own to figure out how everything works.
I have ...
- 219
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Connect VLANs switch SF300 in the same switch
I have 5 VLANs in a switch SF300 configured in Layer3. I Set the switch to general mode so I could connect all the vlans. After 2 weeks that connection has been lost. Now you can only communicate with ...