Questions tagged [vlan]
Group of hosts with a common set of requirements connected as if on the same broadcast domain despite physical location
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How do VLANs work?
What are VLANs? What problems do they solve?
I'm helping a friend learn basic networking, as he's just become the sole sysadmin at a small company. I've been pointing him at various questions/answers ...
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OpenVPN vs. IPsec - Pros and cons, what to use?
Interestingly I have not found any good search results when searching for "OpenVPN vs IPsec". So here's my question:
I need to set up a private LAN over an untrusted network. And as far as I know, ...
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What happens when a consumer switch receives a VLAN-tagged Ethernet frame?
Suppose you connect a trunk port from a VLAN capable network switch to a (VLAN incapable) consumer-grade network switch via a direct cable. Now the former switch send the later switch a 802.1Q-tagged ...
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Why do people tell me not to use VLANs for security?
As per title, why do people tell me not to use VLANs for security purposes?
I have a network, where a have a couple of VLANS. There is a firewall between the 2 VLANs. I am using HP Procurve switches ...
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How many VLANs are too few and too many?
We're currently running a netwok of 800+ PCs and 20+ servers, the network infrastucture is along the lines of Core Switch 10Gb-> Area Switch 2GB-> Local Switch 1GB-> Desktop. All running 3Com ...
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Duplicate MAC address on the same LAN possible?
Let's say someone is on the same network as me and spoofs their MAC address to match mine:
Is this possible? Can two or more clients with the same MAC address be on the same network at the same time ...
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Why does a VLAN have an IP address?
A dumb question for the majority, but I am interested to know "why does a VLAN have an IP address?"
Is this address different from the default gateway? Or is this address, same as broadcast address ...
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VLAN tags not shown in packet capture (Linux) via tcpdump
I am adding a tagged VLAN onto eth0:
#ip link add link eth0 name eth0.20 type vlan id 20
This results in:
#ip link
2: eth0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast ...
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Connect to multiple AP with one Wifi adapter under Linux/FreeBSD?
How can I connect to more than one Wifi access point simultaneously using a single wireless adapter?
I'm currently using pfSense as my home router and I want it to connect to multiple APs wirelessly. ...
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Phones on some switches cannot complete DHCP process
Background
I have a Windows DHCP server (Server 2008 R2) handing out addresses for several scopes. One of those scopes is for some Mitel IP Phones. The phones are configured to use dhcp option 125 to ...
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How can I set up VLANs in a way that won't put me at risk for VLAN hopping?
We're planning to migrate our production network from a VLAN-less configuration to a tagged VLAN (802.1q) configuration. This diagram summarizes the planned configuration:
One significant detail is ...
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Best way to segment traffic, VLAN or subnet?
We have a medium-sized network of around 200 nodes and are currently in the process of replacing old daisy-chained switches with stack-able or chassis style switches.
Right now, our network is broken ...
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tcpdump: capture one of several vlans
I want tcpdump to capture VLAN 1000 or VLAN 501. man pcap-filter says:
The vlan [vlan_id] expression may be used more than once, to filter on VLAN hierarchies. Each use of that expression ...
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Multiple VLANs, multiple subnets, single DHCP server?
At my job we are prepping to transition from multiple LANs connected over slow VPN connections to a single MAN connected over fiber, and I've got a few questions.
First of all, we are planning on ...
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tc u32 --- how to match L2 protocols in recent kernels?
I have a nice shaper, with hashed filtering, built at a linux bridge. In short, br0 connects external and internal physical interfaces, VLAN tagged packets are bridged "transparently" (I ...
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Encryption over gigabit carrier ethernet
My conclusion to this was to pipe VLAN trunks through EoIP tunnels
and encapsulate those in hardware assisted IPSec. Two pairs of fairly
inexpensive Mikrotik RB1100AHx2 routers proved capable of ...
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What do switches do to tagged and untagged VLAN packets?
Let's say we have a 4-port switch that is VLAN capable.
1 2 3 4
Port 1 is TAGGED to VLAN10` and `UNTAGGED to Default_VLAN(1)
Port 2 is UNTAGGED to VLAN10
Port 3 is UNTAGGED to ...
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Does setting MTU on logical interfaces affect physical interfaces
I've been using a combination of interface bond-, vlan- and bridge-interfaces to provide redundancy and different logical network layers to xen domU's.
This setup is working well however i'm a bit ...
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Can switches do VLAN routing? [closed]
I have been learning about VLANs and I am wondering if switch can be used for communication between two VLANs.
Since switches support trunk links and already know the destination/source (VID) of the ...
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Are VLANs necessary for my environment?
I'm the new network manager for a school. I've inherited an environment made up of several Windows servers, about 100 Windows clients, 10 printers, 1 Cisco router, 6 Cisco switches, and 1 HP switch. ...
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How can I setup vSphere so that VLAN tags are not stripped at the vSwitch?
I am trying to test a VLAN-related networking issue, so I thought that firing up a couple virtual machines would be the easiest and cleanest method to test the problem. On the vSphere server I ...
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VLAN for WiFi traffic separation (new to VLANing)
I run a school network with switches in different departments. All is routed through to a central switch to access the servers.
I would like to install WiFi access points in the different departments ...
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Is it possible to connect a single NIC to two different VLANs?
I know it is possible to assign multiple IP addresses to the same NIC as long as they are on the same sub-net (e.g. server A can be assigned both 192.168.1.1 and 192.168.1.2).
However, is it possible ...
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Are VLan's used to split my switch into segments?
I'm trying to plan for the following Small Office network setup:
3x Internet connections
Things connected to the port in each colour can only get routed through their corresponding internet port.
...
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How to add vlan without vconfig command? [closed]
Is there any way how to create vlan interface without using vconfig ? I have only KVM console and trunk port connected to the machine, so I cannot use apt as I do not have internet access. I defined ...
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Can't communicate between lan ports on openwrt router
I've got a WBMR-HP-G300H Buffalo Airstation router on which I've installed the lates OpenWRT software.
All is working well (ADSL, WIFI etc) except for one niggle. I can't communicate between lan ...
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OpenWrt Configuring Tagged and Untagged VLAN on the Same Port
I have installed OpenWrt on a MikroTik Routerboard RB750UP (AR7240 CPU with AR9330 built in switch). I have included additional details below, but my question is:
How do I configure an untagged and ...
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Cisco and Linux and Vlans
I appear to have some fundamental misunderstanding of how VLANs work on Linux, and I'm hoping the good people here can educate me.
Cast: One Cisco 3560, one VLAN, and one Linux box [1].
Cisco -----...
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Architecting your network when you run out of VLANs
This is an entirely hypothetical question, I'm not in this situation now.
What happens to your VLAN topology and routing if you run a multi tenant network and you have more than 4096 customers?
Do ...
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How does VLAN subnetting work on IPv6?
I have a network with about dozen VLANs, most with inter-VLAN routing, some without. They might talk to each other but not to the other's gateway. It's not divided because of security or congestion, ...
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VLAN Inheritance?
Imagine the following scenario:
Primary Switch
|
(VLAN 3 Port)
|
Unmanaged Switch
(Dedicated to IPMI
Interfaces)
|
/ \
/ \
Server 1 ...
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VLAN's - Planning?
Our network is a flat L2.
At some point we need to (I want to, but it's not strictly my responsibility) start to VLAN it down as we're obviously going to have a lot of broadcast chatter going on, and ...
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Send trunk directly to vm in HyperV 2012
I'm setting up OpenBSD as a VM in HyperV 2012. It would be easier for me to just create one interface on the vm and have OpenBSD take care of setting up the vlans.
Is it possible to tell HyperV to ...
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New network design from a noob. VLANS, IP's, hardware, etc. Any comments please
I’m currently planning a large network infrastructure for a University in Ethiopia and would like people’s comments on my planning. Please bear in mind I have never done networking before.
The campus ...
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Windows computers getting SLAAC IPv6 from tagged VLAN
I have windows computers on a network that are un-unexpectedly getting an IPv6 address from tagged VLAN.
I have routers/computers connected to a switch with an untagged vlan (id 1), and a tagged (id ...
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kvm, vlans, how to simulate a 'mirror' port
I'm working with kvm 0.14.1 on an ubuntu lucid x64 box. I've got 3 vlans configured, one that is a bridge to the host's eth1. The others are host only.
I want to start playing with snort. Is there ...
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HP Procurve Issue Passing Multiple VLANs over a link
Just to start off with I am a Cisco guy that got placed into an HP project.
Basic topology overview from outside in:
ASA 5505 with two Ethernet connections to a 2610 switch.
This switch is then ...
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votes
2
answers
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How to set up VLAN network
I'm changing my network from having every device on flat network to using VLans. My problem is that we already have a lot of devices on this network(192.168.20.0/24). From theory, I read that each ...
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Need prosumer router/firewall/vpn/vlan/nat advice [closed]
Looking for a recommendation on a device (or devices I guess) to do router/firewall/vpn/vlan/nat functons for my home network. Right now, I'm doing this with an IPCop box, but I'd prefer a little ...
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Switches - Do I need Spanning Tree?
If I have two switches connected to one another by a fibre link, and each of those switches is also connected into a local switch, and those two local switches are linked, I'm correct in thinking that ...
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Looking for a tool to plan network/vlan topologies [closed]
I'm looking for a tool (desktop or web-based) that we can use to plan our network topologies using VLAN's. Something capable of defining switches, and mapping VLAN's to the ports and allowing use to ...
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Linux NIC bonding on top of vlan interfaces?
Is it possible to set up bonding(active/backup) on top of existing vlan interfaces ?
Assume the following scenario:
Linux Server with 2 NICs connected to separate switches
iSCSI initiator + MPIO to ...
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How to configure a HP Procurve network for IPv4+IPv6
The setup:
We are an apartment complex with approximately 1700 units. Every apartment has internet with an ethernet plug in each. The network has 60 HP 2910al-48G switches connected to a central HP ...
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Linux Router Problem
I have a Linux based router with four interfaces (each with its own private subnet).
When I directly connect a device directly (i.e. no switch, just a patch cable) to one interface and another device ...
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Is there a good way to programmatically configure VLANs on a managed switch?
My situation is that my company makes a product that (currently) requires the user to set up a dozen or so VLANs on a managed switch that is dedicated to the exclusive use with our product.
Currently,...
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Arbitrary VLAN interface name
Is there a way to name a VLAN interface arbitrarily like eth72 or ext19 instead of the four standard nameing schemes eth0.72, vlan19 (and the padded variations)?
Don't have no clue. Perhaps udev?
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Putting Android on ethernet network using VLAN s
In our lab, we have static IPs assigned to everything. We have less than 20 devices, some physical and some virtual on ESXi, ranging from servers to android tablets. Everything is wired ethernet. ...
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When to use routers and when to use layer 3 switches [closed]
If you were to connect two buildings on the same site via fiber, what is best to use - routers or layer 3 switches? The layer two switches in each building have VLAN's, so these will either connect to ...
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Can I connect a servers from Hetzner cloud to a vswitch
I have some dedicated root servers at Hetzner wich are connected via a VLAN using the vSwitch. Now I would like to know if you can connect servers from the Hetzner Cloud to the same vSwitch so they ...
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Best Approach for subnetting/VLANing traffic?
Our network is currently setup with no subnets or VLANs. We are looking at going to VoIP so this needs to change before VoIP is installed. I believe that we want to use VLANs to separate Voice and ...
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