a device that bridges network segments, operating at the OSI link layer level.

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-3
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1answer
62 views

Router Switch hanged down [closed]

I have a switch placed in department and connected through Media Converter which is directly connected through optical fiber cable from 3com Switch. Now the issue is Some times suddenly the Endpoint ...
5
votes
3answers
2k views

Can internet gateways be plugged straight into a layer 2 switch?

tl;dr Internet gateways (eg., cable modems, fiber optic gateways) don't function properly when they aren't behind a device with "layer 3" or routing capabilities, correct? Incredibly long backstory ...
5
votes
1answer
278 views

HP 5500 switch manual states SNMP traps impact performance and advises against their use unless “necessary” - why?

We just bought two HP 5500-24G-4SFP beasts and I'd like to properly integrate the switches into Nagios. Most of our current monitoring polls actively via SNMP so I figured it would be wise and use the ...
6
votes
3answers
13k views

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 ...
0
votes
2answers
8k views

How to set up 2 separate VLANs on one switch (HP v1910-48G switch)

I need some advice on how to set up 2 VLANs (on one switch, I have HP v1910-48G switch) that separate broadcast domain and also share a single internet connection. The two Vlans must remain separate, ...
0
votes
1answer
120 views

Cisco switch restart doesn't reload config

Something really strange happened to me today. I was configuring a 3750 switch and halfway through the changes I messed up. So I did what I've always done, unplug the power cable from the switch and ...
0
votes
1answer
98 views

Can a home router separate private network? [closed]

I've just come across this network diagram: http://computer.howstuffworks.com/router1.htm And I am thinking if it can be done with a typical home router. Normally for home router, when we plug a ...
2
votes
2answers
83 views

Cisco Switch went mad

tI have a Cisco SLM2048 Smart Switch which I can't access anymore. The switch is working just fine but: I can't reach it by web interface Doesn't seem to be able to reset it, even if I hold reset ...
1
vote
1answer
538 views

LAN Redundancy - NIC, Cables + Switch?

I'm trying to move to a HA solution and would like to understand what hardware is required to have redundancy in the NICs, switch and cables. The diagrams below show how I envisage a non-redundant ...
1
vote
2answers
99 views

LAN routing without vlan tagging?

On my old Allied Telesis router I had a single interface for internal traffic. I had multiple networks talking on this one interface. For example 192.168.2.X was vlan 1-2, and 192.168.3.X was vlan ...
2
votes
1answer
12k views

Configuring VLANs on HP 1910 switch

I understand how VLANs work, but am not quite sure what the various settings in my HP switch actually do. I have an HP 1910 switch, and I'm using the web interface to configure it (personally I'd ...
1
vote
0answers
110 views

Routing between L2 isolated ports

I am to deploy some managed switches for FTTB/FTTH and preparing configuration to introduce isolation between customers (by disabling L2 forwarding between client ports or using private VLANs). ...
1
vote
2answers
117 views

Avoiding switch loop

Will I have loop problems with this topology because S2 and S3 are both connected to S1 and s4 ?
9
votes
1answer
1k views

Proper method for connecting multiple non-stackable network switches?

I deal with many clients in warehousing and industrial applications who have IT staff or local consultants. Many of these sites are still using a 10/100 Megabit switching backbone... I've managed to ...
-1
votes
1answer
35 views

SMB Server & Switch

I am by no means a server professional, that is why I am coming to you guys for advice. Our company is looking to purchase an office building that is currently wired for ethernet. We are going to ...
12
votes
3answers
1k views

Improvements for small business network?

My question is more-or-less a newer version of this 3 year old question: Small Business Network Switches/General network configuration Summary Everything is Gigabit and we don't have any real ...
2
votes
0answers
112 views

How to fix an aborted firmware upgrade on Cisco SLM2048

There is a Cisco SLM2048 switch and the last firmware upgrade aborted, now the switch doesn't work anymore. I can't access the switch. The only evidence is a blinking system LED. As the switch doesn't ...
2
votes
2answers
196 views

Colocation, Full Rack, Layer2/Layer3 Clarification

We are moving from several 1U servers colo'ed out across several data centers to a full rack in a nearby data center for both physical access reasons, as well as having space for expansion. We also ...
0
votes
1answer
303 views

Multiple DHCP servers on a single physical network?

Today i got put on a project to solve a networking project for a friend who rents out multiple office suites. Internet is provided to all suites in the rent cost. The guy who originally set everything ...
1
vote
2answers
303 views

Is VLAN separation required for multiple networks?

I am setting up a Dell 6248 combining separate switches used previously. I am planning the following architecture: VLAN 1 - External traffic (each server's public interface connects to this) VLAN 2 ...
0
votes
1answer
34 views

HP equivalent of the the FindIT Utility

I think I've lost the configuration on two of my HP-Procurve 1810-24G. I can't connect with either the previously assigned static or the or the default factory ip. Are there any utilities equivalent ...
1
vote
1answer
40 views

Backup slowness after changing the SAN switch

We have a netbackup environment Recently we changed the connectivity of two of our sql servers(cluster servers) from one SAN switch(MDS 9509) to another (MDS 9513) followed by which we are ...
1
vote
2answers
2k views

How to connect two HP 1910-48G switches

My company have two HP 1910-48G Switches. One of them is on my flat and the other one is two flat above. I'm not a network guy but my manager wants me to connect these switches and he doesn't want to ...
-1
votes
2answers
97 views

Connect four Modems having same IP with a single Ethernet Switch [closed]

I have a scenario where i have 4 modems connected to a switch. all four modems have IP address 192.168.0.1(default). i want to connect all of these four modems with a single switch in a way that i ...
0
votes
2answers
71 views

Commercial Routers with internal switch [closed]

I often confuse "commercial" routers (which include switching, dhcp, firewall, etc. functionality) with "academic" routers (strictly layer 3). My question can be summed up in the following image: ...
1
vote
1answer
116 views

Finding a network switches IP

These are not Cisco switches or switches with serial cables. They are also on a live 24/7 business network. I was tasked with doing some network work but I don't know the switches IP address and ...
3
votes
3answers
2k views

Is there a way to pass VLAN tagged frames through managed switch?

I currently have a managed switch (DGS-3120-24SC) configured for private VLANs (secondary and primary port groups). Secondary ports are isolated from each other and forwarding is not possible between ...
0
votes
1answer
79 views

How best to setup for high traffic due to thin clients

I develop a client/server software system that is designed to display images to the photographer's customers. A LOT of my customers are using thin clients for the viewing stations, the NComputing ...
1
vote
0answers
243 views

why do I lose ping to a machine when using port mirroring / monitoring (sniffing)?

I am using port mirroring / monitoring in my 3COM layer 3 switches to look at network traffic (using wireshark). Sometimes, I have found that I loose connectivity with the remote monitor machine ...
0
votes
3answers
122 views

is this network structure viable?

I would like to know if this network structure it would be viable or not. The main reason it would be to be able to switch manually, the ISP. If one is going down than use the other one. as I know ...
2
votes
1answer
161 views

What could be wrong with my VLAN?

I've got a VLAN 10 setup as a management VLAN. The management VLAN comes off port 48 and links to another set of switches that do not support VLAN's so it was I believe set up as an untagged access ...
0
votes
1answer
41 views

Seeing odd (to me) packets in a network capture

This morning I connected a system to our switch connected to our ISP handoff in order to do some wiresharking. I had yet to set up any port mirrors, and confirmed that there were none in place. ...
0
votes
2answers
50 views

switch duplicates packets and forward in two route

there is a network including a router, two hosts and a switch which connects hosts to router. i have a virtual machine on my system. the network adapter is set to act as bridge. so the virtual machine ...
0
votes
1answer
98 views

Only one server behind a switch cannot access the internet and vice versa

I have multiple servers deployed behind a single switch. All the servers have their own public IP addresses. Suddenly one of them (say A) cannot be accessed from the outside by any means, e.g. HTTP, ...
0
votes
1answer
152 views

can network Redundancy possible with help of Layer 2 switches & dual NIC in one PC & program in java?

I am Trying to achieve Network Redundancy in network which have 1 server & lots of node which use 1 switch for each. As per various forums for achieve Redundancy in network i should use Layer 3 ...
1
vote
0answers
64 views

Juniper 802.3ad Link between Switch and Router 3x link issue

We have a live 20Gbps link between our switch and router and we are trying to add another 10Gbps link to the LAG, we've changed all the settings on both end to add the third interface to the LAG yet ...
0
votes
1answer
455 views

UDP packet loss on Netgear GS110TP

I'm trying to flow data via UDP on two ports of a Netgear GS110TP switch, running the latest available firmware (5.4.2.9). However, I'm experiencing a small amount of packet loss, something like ...
0
votes
1answer
98 views

Private DHCP through a switch using two eth interfaces?

Right now, I have an Scientific Linux blade connected to the internet on eth3, and connected to a 48 port Cisco switch on eth2. This Cisco switch is connected to the eth2 of 24 blank blades (which are ...
-2
votes
3answers
78 views

can power on ethernet for one poe swtich to another layer 2/3 switch?

My question is 1. can we use 1 poe switch as power supply for another layer 2/3 switch? 2. If question 1's answer is yes then What should be maximum distance between those? As per my reading in ...
1
vote
2answers
391 views

How to add multiple IPv4 Subnets to a VLAN using Allied Telesyn at9924 Switch?

I cannot figure out adding more than one IPv4 subnets on a VLAN using Allied Telesyn at9924 Switch I've added the first IP using this command: add ip int=vlan15 ip=xxx.243.117.193 ...
-2
votes
1answer
99 views

Why do collision may occur if there is duplex mismatch?

In a question on Serverfault It is mentioned that "it is possible for a single host connected to one port to experience collisions if there's a duplex mismatch between the host NIC and the switch port ...
1
vote
3answers
298 views

Cisco Switch Out-Of-Box without console access

I have a Cisco C2950-24 Switch Out-Of-Box here. But my laptop doesn't have serial port nor I have the console hub. Is there a way to setup the switch from this state without console access? I have ...
0
votes
1answer
596 views

Cant Connect/Ping to Management Console on Cisco SG200-50 after Connecting networking

I have two of these switches. When I have nothing else plugged in and a cable from port 1 to a laptop on the same subnet I can connect fine, however after plugging any additional networking in I ...
-2
votes
1answer
26 views

Uninstalled server 2008 now router won't handle DHCP

My set up is this. server behind router, router has a server and switch connected to it with multiple computers. router used to serve DHCP and DNS, a couple of days ago installed AD, DNS and DHCP on ...
0
votes
1answer
54 views

Move single ip address accross network or virtual machines

I'm currently trying to set up a small development cluster inside our enterprise network. We have a system to provision "disposable" virtual machines and move them to any of our 12 servers if needed. ...
4
votes
1answer
714 views

HP Procurve 2512/2524 protected port, source port filter or similar?

HP Procurve switches usually have a setting so that the ports are told which other ports they can communicate with. An easy setup using this is to only allow communication with the uplink, so that no ...
0
votes
1answer
63 views

Which would be the best switch for a cloud cluster? [closed]

I am about to set up a private cloud using Eucalyputs on CentOS, and I am confused about buying a network switch. Right now there will be 4 node controllers on my cloud, but in the near future I am ...
0
votes
0answers
301 views

Computers Suddenly Lost Connection to SBS 2008 Server

I am having an issue that I could not explain myself in the entire of my career. The issue is when the entire computers just randomly and suddenly lost connection to the server, running Windows Server ...
1
vote
1answer
76 views

Monitoring bandwidth on a layer-3 invisible switch [closed]

Our servers are distributed to 2 racks in a datacenter, each rack having its own switch. The communication between the racks are made by the link between these two switches. The bandwidth between ...
2
votes
1answer
732 views

switch, procuve 2510, error: OS TFTP in prgrs, SNMP denied

I cannot reboot 2510-24 then I get this message: OS TFTP in prgrs, SNMP denied Smart as I am I just started a new TFTP download of latest firmware, but that is a no-go since another download is in ...