Switches / Hubs





A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

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I am setting up a SOHO.
Equipment is as follows.
1)  4 security cameras that record to the cloud through a Northern system
2)  Home wireless system mesh network
3)  Usual computers,  printers, etc
4)  Other "internet of things devices"  such as thermostats, lights.
5)  I have a total of 10 Ethernet jacks in our home, but only 6 in current use.

I will be installing a 19 inch 6U Wall Mount Patch Panel Bracket - 13.75 inch deep (also 24 port Cat 5E patch panel etc)
Gigabit internet.

I have concerns about putting all these things on one switch.  I like the idea of segmenting my network.  
I have heard good things about the Ubiquiti.  I am not an expert on routers, but I not a unfamiliar either.  
I am thinking about a router/switch capable of VLANS and POE for the cameras.  If I am misguided, then new insights are welcome.

With that in mind,  I would appreciate any help in selecting  a router / switch that would be appropriate but not more expensive than I need.

Thank you for your help.
Learn SQL Server Core 2016
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How to backup the existing running configuration of Cisco routers and switches? So that l can load the configuration to another replacement device if failure
I'm experiencing a Linux routing problem.

Environment is SLES 12 SP2, running on some HP server machine with 8 physical, used network interfaces, running in a non-internet local network.

Most physical network interfaces (eth0 ... eth3 and eth5 ... eth7) have (local unique) static IP addresses in non-overlapping networks, and the routing table looks ok. The interface eth4 is on DHCP.

The problem is that sometimes packets seem to be sent over the wrong interface - a packet that is expected to fly thru eth6 is spit out on eth0. This happens erratic and causes to application software (managing measurement data) to loose the data stream after max ~15 minutes .

As fa s I can see,

  • the exit interface of the wrong-routed packets is always eth0
  • there are packets of at least 2 interfaces routed wrong
  • the configuration of eth0 (viewed by YaST and by inspection of /etc/sysconfig/network/ifcfg-eth0) shows no IP addresses from the other interfaces networks

If I take down eth0, the application runs smooth (but that's only acceptable for testing matters).

If I record the network traffic of the network addresses for eth2 (tcpdump), I find i.e. suspicious ARP requests originating from address on eth6 with an originating MAC address of eth0.

Any idea what happens here ?
Any idea how to fix it ?

P.S.: Due to some policies demands, I can't do any driver etc. updates on the system. Same appies to ideas like "do DHCP on all interfaces" ... I can't change that.
Restoring an Archive File to 2960

I can successfully transfer a file to and from my Cisco 2960 switch. I have an archive function in my configuration and it works great. I am trying to restore a config from my backup location to the flash on the switch. I can successfully SCP from the switch to my backup location and transfer the files to the switch flash. The file shows/ displays there. However, the file size on flash shows zero / 0.

I have verified the contents of the config in notepad. The file size, when viewed from computer, is 13 KB. I can open in notepad either using a .txt or .cfg extension.
Physical Parts of Control/Data/Management Plane.

reading about Control/Data/Management Planes , if I understand :

Control plane is where the Routing table is built.
Data Plane or also called Forwarding plane contains a copy of RIB
Management Plane , I am not sure what it is, probably it is just the interface of the router or the switch to which we connect to.

What I need to know, is the hardware that the above elements run on.

for instance does Control  plane encompasses CPU , Memory , or it is completely different Chip ? the same question applies for Data plane and Management Plane, on which hardware do they run on?

Thank you
Need to set up a ring topology using ubiquiti switches. The area to be covered requires about 400ft between each switch. How do i configur the switched to do this ?
Above link mentioned it's the IOS that will be EOSL.

What's the EOSL date for Cisco 2960x hardware itself & what's the replacement model?
We need a model that has 48 more months at point of implementation.
I have multiple Cisco swithces 3850's and 2960's in my envirronment.  I am using port channels on some, but is there a command to tell if LACP is enabled on every port on a switch or certain ports only?
I need to clone/copy a Cisco 2960 layer 3 switch config to an identical Cisco 2960.  I need to also copy the layer 3 configuration (routes, vlans, etc).  Anything I have seen only lets you copy the layer 2 config.  Yes I tried to Google the problem first, but there is not much I can find on how to do it.
Any help would be appreciated, thank you.

hi guys,

At the place I work at, we have a primary internet line and a secondary internet line. The secondary isn't being used as it is a failover. However, the primary line  with a Cisco 1941 has got its CPU usage to almost 90% every single day. The secondary line is not being utilised at all. That also has a Cisco 1941.

We have a change freeze window coming up for almost 2 months! So we can't do anything from this Friday onwards.

The future plans will be to upgrade WAN bandwidth and change the Cisco routers. But for now, if I wanted the secondary line to become utilised, would you use a Meraki Mx68 to do the load balancing? So that it would sit in front of the two routers and it would load balance the traffic to one or the other to turn it into an SD-WAN capable system?

Are there any other ways that you can think of?

Thanks for helping
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Hi PC is plugged into switch 2900. sometimes we cannot see the PC mac address when using command --show mac address. Do you think it is possible if the port and PC are in good status? Thank you
We are going to be getting 1000Base-LX from provider but customer is all cabled up w/ MMF wiring and MMD SFP on router, the device is at around 100Mts from the demarc. Can you please shine some light if this setup will work, the change is going to cost and was wondering if there is a real need for a change?


Everything went ok apart from 1 question I have:

upgrade to same IOS - done
set priority to 1 to be member - done
write erase - done
delete vlan.dat done
backup run config of stack

stacked the 3rd switch correctly
powered on added switch
current joined stack not powered down
switch came up as stack - sh switch shows as member

now not sure if this is normal but none of the new switch interfaces had any VLAN assigned in their config.
I did a int range and assigned them all -so no big problem. However I was expecting them to be picked up and configured from the master. So is what I have experienced normal??
Good day all,

im trying to make a Batch file that Copies Dell Switch Config to the Switch.
The Config is in .txt Format so im trying to setup a Batch File that Copies the Config and login to the Switch Via Kitty/Putty and past the config.

Thank you in Advance.
I'm dealing with performance issues with a VOIP phone system.
The VOIP service provider provides a dedicated internet connection for VOIP and the "PBX" is externally provided by the VSP.
Since the PBX is external, even internal extension-to-extension VOIP calls cause external traffic.
We provide a dedicated VOIP firewall in the form of an RV320 followed by cascaded SG300 switches - configured with a VOIP VLAN with QoS set up.
We provide a dedicated internet connection and firewall for site data - independent of VOIP traffic.
There are 3 sites, each one with separate internet connections, firewalls, etc.
The largest site has about 20 phones and 25 workstations.
The smallest site has about 6 phones and 10 workstations
The middle site has about 9 phones10 workstations.
Data traffic is modest.

I believe the VOIP system is working overall as intended so the "problems" are a matter of service quality I'd say.
Problems are intermittent and include:
- audio is heard at one end and not the other.
- a very loud "screeching noise" is heard at one end or the other and can be audible at one or both ends.  This is reported to be rather high-pitched and not like loud TV white noise.
- some incoming calls don't arrive on site and go directly to voice mail.
Overall, it's reasonable to say: "while the system seems to "work", service is unacceptable".

Since the 3 sites are each independent of the other re: VOIP, if all sites behave similarly (re: problems) then one might …
I am trying to understand how SD-WAN helps SaaS connectivity for an enterprise company.  What I know only that SD-WAN is used for WAN connectivity between Main and Remote Offices.
For example if I am located at branch office and wants to connect with Office 365 then how SD-WAN make a connectivity with Microsoft Cloud ?

Can someone please shed some light on this ?
EEM v 4.0 on Cisco 2960.

I am trying to no out my EEM Events on my Cisco 2960 but I can't determine the name!!!

SW1(config)# do show event manager history

That does not show the complete file name! I need the entire file name to remove it from EEM.

Hi ladies and gents.  Has anyone worked with Datto's AP using Cisco Switches?  Currently we have about 10 AP's that are meshed within the organization all communicating with Cisco Switches.   However 1 AP is constantly spamming MAC addresses to the switch which is showing the following.

001247: Oct  9 10:07:12.401: %SW_MATM-4-MACFLAP_NOTIF: Host f439.0917.a34c in vlan 3 is flapping between port Gi1/0/24 and port Gi1/0/14
001248: Oct  9 10:08:33.671: %SW_MATM-4-MACFLAP_NOTIF: Host b00c.d14b.decf in vlan 3 is flapping between port Gi1/0/24 and port Gi1/0/8
001249: Oct  9 10:08:52.445: %SW_MATM-4-MACFLAP_NOTIF: Host 84a9.3e46.1588 in vlan 3 is flapping between port Gi1/0/24 and port Gi1/0/6
001250: Oct  9 10:09:52.236: %SW_MATM-4-MACFLAP_NOTIF: Host 10e7.c6b6.51a3 in vlan 3 is flapping between port Gi1/0/24 and port Gi1/0/12

We have spoken with Datto about this and they had suggested a few things such as disabling mesh and internet listening since they are all on the same domain which we have done.   We have also flashed every AP to 6.5.2 which is the latest firmware on the AP from 6.4.15.   MACFLAPPing continues.

Datto had advised us to change the settings on the switch from flooding to filtering which we did and caused havoc with our phones so we had to re-enable flooding.   All the other AP's are perfectly fine and do not spam any of ther other switches with MAC addresses.   I have factoried the AP reflashed the firmware and it is still happening.    The device is…
Hello All,

I've been tasked with getting clock equipment working on our campus network. I need to have these touch screen stations in the same broadcast domain as the master server ....but the server reside under server block.

Server block access switches are connected to a distribution switch and DSW are connected to Core Switch over L3 links
Clock devices are connected to access switch trunked to Core switch
What's the best way to span a layer 2 broadcast domain over a layer 3 routed uplink??
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Hi Folks,

I am just wondering how to decide the location of wireless access points in a building while it is not yet ready. We just got floor plans and we need AP locations and handover to buildinc contractor for cabling.
We need to enable proper wireless coverage in our 4 floor building
We will be using Cisco Wireless Access Points 9115ax with Cisco 3504 controller.

Any thoughts
It is better to have  two 24-port patch panels or one 48-port panel?.  We are making a single IDF closet for 4 floor building and all UTP cables will run to single closet. As per cabling contractor, the cables are under 90m length.
IDF is currently designed to have 12x24 patch panels and 7 access switches.
Also is it good idea to have single IDF closet ?

Any thoughts ?
We delivered MMD handoff instead of Electrical to customer and they think we should bring media converter, their end device is Cisco 6509E. Does this device have optical ports for connections?
Hello Experts,

We are planning for a network infrastructure upgrade. It includes structured cabling and active systems.
The network is currently running Cat5e cables, patch panels and faceplate modules.
Cisco Catalyst 3560 is deployed at edge and 6506 at Core.
We want to upgrade the infrastructure to Cat6a structured cabling, Fiber cabling supporting 10g and Cisco Switches with  SD-Access.
Therefore, we are looking for tips and suggestions to start preparing the plan.
I'm looking for some help re-configuring my home network. Here is current setup:

Comcast cable comes into data enclosure in garage wall to a 2-way Splitter. One coax goes to Gateway in my office. Patch cable out of Gateway to a switch beside it which connects my desktop and network printer. Patch cable from this switch to the wall jack backfeeds back to the data enclosure in the garage. Patch panels in the data enclosure connect to small switch in the data enclosure to provide network to other jacks in house.

First, I'm planning to ditch the Comcast Gateway and go with my own modem and router. I want to add a Ubiquiti Cloud Key Gen 2 Plus and eventually a couple of security cameras as well. I'd like to centralize things a bit more instead of going to my office and then backfeed to the data enclosure before distributing to the rest of the house. Unfortunately, there isn't room in the data enclosure for the router, modem, etc. and even if there was, I'd be concerned about the temps. It can get pretty hot in the garage (90F+).

The room directly above the data enclosure in the garage is a storage room with heat and A/C. Perfect location for the network equipment. And it has a knee wall I can get behind and access the cables going down into the garage.  But I'm not sure how best to proceed.

There are 17 Cat5e cables coming into that data enclosure in the garage, 7 from top (upstairs jacks) and 10 from bottom (downstairs jacks). There appears to be enough length on the …
On Cisco core switch 3850, I need to get a list of end devices IP address and it associated port on the switch

Switches / Hubs





A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.