Switches / Hubs

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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 have 1 aruba 2930F 48G 4SFP+, 2 24G POE+ 4SFP+ switches. How should I stack them?
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Hi Experts,

on my CISCO switch I have connected 3 access points.
I just know the IP and MAC but I need to know the switchport.

How to find out what is connected on the switchport ?
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Hey guys. Hope you might be able to help me out with this sort of...unique situation.

We have two facilities. I'm trying to set up some VLANs, but there's a catch: we have a fiber connection between the two buildings that is causing some problems. Let me give you an outline of our layout.

Internet comes in from ISP to a Cisco RVS4000 router/switch, plugged into WAN. Port one has a cable connecting to the main switch (Cisco) of Facility 1 (F1), which has a DHCP server running Windows Server 2008 (unfortunately. I have a new server to setup when I'm done with this project to fix that). Port three has a cat cable connected to a fiber converter going to single mode fiber running to Facility 2 (F2) about 10 miles away. (That connection is working flawlessly. I can plug into the main switch and be on the same IP range and domain as though it's just a long cat cable, because essentially it is.) At that facility, it's plugged into port 8 of a Netgear (I know) GS510TLP and running to a TP-Link (I know) T1600G-52PS. Port 2 on the Netgear is going to a TP-Link T2600G-28MPS for VoIP and port 3 is going to a T2600-28MPS for cameras.

I created some DHCP scopes and VLANs (VLAN 2 and 3) between all this mess and got it sort of working. By sort of, I mean I can plug into the switch at F1, and VLAN3 will give me a DHCP address from the server. VLAN2 will not. In order to do so, I had to use two other NICs in the DHCP server on the ranges (4.x and 5.x) I'm needing for those …
0
I have network diagram where we have replace the cisco switches with Aruba switches. We got the current cisco config so we can configure the new Aruba switches accordingly. Can someone help me to share a project plan template or something similar for the implementations. All the cabling will be in place on site and all the devices, spf modules will be there.
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I'm looking at ordering some products from www.perle.com and wanted to know if they have good quality products?

I need to get a terminal server for my switches and also I need to run IP cameras over 328 feet, so those ethernet extenders look like would be a fairly easy way to do that.

Part numbers:
exp-1s1110L-rj
exp-4s1110L-rj
IOLAN SCS48c

Any thoughts, is there a better way to accomplish this?
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On a Cisco switch what is the best way to tell if a port or interface is enabled or disabled by using no shut pr shutdown.

Thanks
0
I am trying to setup a port channel between 2 cisco 2960s.  

I am using the following:
Switch2#(config) int port-channel 1
 Switch2#(config-if) switchport mode trunk
 Switch2#(config-if) switchport trunk encapsulation dot1q
 Switch2#(config-if)!
 Switch2#(config)int range gig 0/45-48
 Switch2#(config-if) channel-group 1 mode active
 Switch2#(config-if)!

The problem is  I get Invalid input detected at

 #switchport trunk  encapsulation dot1q
                                   ^
 % Invalid input detected at '^' marker


Could someone tell me what I am doing wrong?
0
I am facing below issue

please suggest why this is happening.

24-Dec-2015 16:14:00 %LINK-I-Up:  gi28
24-Dec-2015 16:14:01 %LINK-W-Down:  gi38
24-Dec-2015 16:14:03 %LINK-I-Up:  gi38
24-Dec-2015 16:14:05 %STP-W-PORTSTATUS: gi28: STP status Forwarding
24-Dec-2015 16:14:06 %LINK-W-Down:  gi48
24-Dec-2015 16:14:07 %STP-W-PORTSTATUS: gi38: STP status Forwarding
24-Dec-2015 16:14:08 %LINK-I-Up:  gi48
24-Dec-2015 16:14:10 %LINK-W-Down:  gi17
24-Dec-2015 16:14:12 %STP-W-PORTSTATUS: gi48: STP status Forwarding
24-Dec-2015 16:14:13 %LINK-I-Up:  gi17
24-Dec-2015 16:14:13 %LINK-W-Down:  gi22
24-Dec-2015 16:14:14 %LINK-W-Down:  gi11
24-Dec-2015 16:14:14 %LINK-W-Down:  gi36
24-Dec-2015 16:14:14 %LINK-I-Up:  gi22
24-Dec-2015 16:14:15 %LINK-I-Up:  gi11
24-Dec-2015 16:14:16 %LINK-I-Up:  gi36
24-Dec-2015 16:14:17 %LINK-W-Down:  gi40
24-Dec-2015 16:14:17 %STP-W-PORTSTATUS: gi17: STP status Forwarding
24-Dec-2015 16:14:19 %LINK-I-Up:  gi40
24-Dec-2015 16:14:19 %STP-W-PORTSTATUS: gi22: STP status Forwarding
24-Dec-2015 16:14:20 %STP-W-PORTSTATUS: gi11: STP status Forwarding
24-Dec-2015 16:14:20 %STP-W-PORTSTATUS: gi36: STP status Forwarding
0
I'm attempting to connect some switches in my IDF locations to my MDF switch via SFP.

The fiber connecting each IDF to the MDF is multimode, OM3. It connects to a LANscape housing in each location. From the housing, I'm trying to connect a fiber patch cable to the SPF module on the switch.

I managed to get ONE switch working in ONE IDF by using an aqua OM3 patch cable connected to a Ubiquiti module. The only way I could get that connection to work was with a multimode fiber converter in the MDF connected to a port on the switch. SPF would not work. I've tried various SFP modules, including an SPF+ 10G multimode, a Trendnet 1.25G multimode, a generic 1.25G multimode module, and even a couple single mode SFPs, just in case. I've tried aqua OM3 patch cables, orange OM1 patch cables, various LC to SC adapters, and some yellow single mode patch cables, again, just in case. I've tried just about every single combination of the above in some fashion.

On a second switch in a second IDF, even with a fiber converter in the MDF, I can't get a link. If I remove the converter from the first connection in the first IDF, I can't get a link with any combination of the above.

I am about to go insane with this problem. This should be straightforward and easy, but it's driving me nuts.

The contractor installing the actual fiber backbone has told me it's multimode fiber, OM3, 50 microns. I suppose that might be incorrect information, but I have had no issues or inconsistencies …
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Long story short, at the bottom of my Cisco 2960 switch config I want to:

1) add the line:  logging esm config

2) delet the line: transport input none


  Can someone show me how to do?

I want to do this to exactly match a config I copied from.
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I am going to trunk 2 cisco 2960s via cat 5.  I already copied the config from switch 1 to switch 2.  trunks and ports are setup.

My question is, the crypto key on switch 2 now looks a little different that switch 1 (since I copied I thought it should be the same?)  The first few lines are the same, but then it changes.  Is this ok?  Do I need to generate another crypto key for the second switch?  Or since the first switch already has a crypto key, do I even need another one?
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How Telnet works in GRE Tunnel

t
in the topology above I have created a GRE tunnel between R1 and R3. The configuration is shown below:
R1#show running-config 
Building configuration...

Current configuration : 2295 bytes
!
! Last configuration change at 09:31:13 CET Wed Sep 5 2018
!
version 15.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
aqm-register-fnf
!
!
no aaa new-model
clock timezone CET 1 0
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!
!
!
!
!


!
!
!
!
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!         
!
!
redundancy
!
!
!
class-map match-all MAPMYGRE
 match access-group name MYGRE
class-map match-all MAPTELNET
 match access-group name MYTELNET
!
policy-map MYPOLICE
 class MAPTELNET
  police 128000
 class MAPMYGRE
!
! 
!
!
!
!
!
!         
!
!
!
!
!
!
interface Loopback0
 ip address 1.1.1.1 255.255.255.255
!
interface Tunnel0
 ip address 172.16.13.1 255.255.255.0
 tunnel source 192.168.12.1
 tunnel destination 192.168.23.3
!
interface Ethernet0/0
 ip address 192.168.12.1 255.255.255.0
 service-policy output MYPOLICE
!
interface Ethernet0/1
 no ip address
 shutdown
!
interface Ethernet0/2
 no ip address
 shutdown
!
interface Ethernet0/3
 no ip address
 shutdown
!
interface Ethernet1/0
 no ip address
 shutdown
!
interface Ethernet1/1
 no ip address
 shutdown

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Hello,
I have the topology (upper one in the figure below) where an ESX is directly connected to a Cisco Router. And the link between the two, is TRUNK link handling three VLANs.

I would like to use a Cisco switch c2960 between the router and the ESX server to connect other servers to one of the VLANs.  (lower one in the figure above)
Configuring the ports of the Cisco switch as trunk ports didn't help.
I would like to know what i should do to make everything work correctly.
Thank you.
0
Fortigate 200D in HA cluster

i have a problem (user "accidentaly started wizard" to change gateway)....

and fortinet stoped routing as expected, as it seems nothing has changed.
static routes are the same as before, route lookup hits the right route, traffic seems to hit the right policy.

Monitoring the traffic it says       "Accept: session timeout" for everything

i can ping port to internal network from CLI, i can ping something on Internet (WAN) from CLI

but nothing gets thru from external(WAN) to internal network (PORT1) or viceversa
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This is about the switch infrastructure using Cisco switches. Currently, there is only using one Cisco WS-2960x-48 POE switch. We also using Cisco UCS 500 series for the VOIP. We are using vlan 101 for data, and 102 for voice. Please see the attached cisco switch configuration.

Now, we intend to buy one new Cisco Meraki MS120-24 ports switch, and join this switch into the switch infrastructure. We also intend to add-in 2 more VLANs for our new VMware virtualization management and backup segments. This is a new 2-hosts virtualization (vmware), with 2 network ports to form a trunk carrying existing vlan 101 (data), management (vlan 121), and backup (vlan 122) from each host. How should I update in my existing POE switch and also the new Meraki switch? Can I make all the 3 vlans - 101, 121, and 122 routable but only allow selective ip to access. For example, only allow 192.x.x.25 to access all vlan 121 & 122 only, but not the other way round.

Thanks in advance.
Cisco-2960-48-POE-Switch.txt
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A ubiquiti Fiber switch connected to a Meraki MS 42 is showing VLAN mismatch errors.  

from the Ubuquit, two fiber ports are aggregated to two 10G fiber ports on the meraki.  Meraki says there is a VLAN mismatch.  I cant see the discrepency.  Any thoughts?  Have rebooted Unifi Controller, fiber switch, meraki etc.

Untitled.pngCapture.PNGCapture.PNG
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Precedence in Cisco Qos:

in QoS Precedence, there is a list of precedence settings as shown, below.. I would like to know in which case should I select which precedence in the list..
For instance , in case of Voice, or Video, or specific protocol HTTP or HTTPS or FTP or TELNET or SSH, etc how  would I know which on this list to select ?

Thank you


R2(config-pmap-c)#set precedence ?
  <0-7>           Precedence value
  cos             Set packet precedence from L2 cos.
  critical        Match packets with critical precedence (5)
  flash           Match packets with flash precedence (3)
  flash-override  Match packets with flash override precedence (4)
  immediate       Match packets with immediate precedence (2)
  internet        Match packets with internetwork control precedence (6)
  network         Match Packets with network control precedence (7)
  priority        Match packets with priority precedence (1)
  qos-group       Set packet precedence from QoS Group.
  routine         Match packets with routine precedence (0)
  tunnel          Set tunnel packet precedence

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0
Hi,

I've a question in relation to setting up VLANs.  I need to add another subnet to my network, I would like to separate out our HR dept (to begin with, the others will follow) and to free up some IP addresses on our existing Subnet.  I have four switches, two are Cisco SG 200-50, the other is a Cisco Catalyst 2960-X and the last one is a Catalyst 3560-CG.  I also have an MPLS router with our third party company to connect to the rest of our sites.  I've created a number of VLANs on the 3560, one for our HR Dept, one for management and a few others that I'll use later down the line.  My question is, how does it all fit together.  I'm aware the the 3560 will be carrying out the routing of the VLANs but should I have trunk links between all the switches (the HR folk will be connected via the 2960)?  Should the 3560 be direcly connected to the MPLS router, if not and I plug it directly into another swithc, surely that would create a loop.  I have the basics down (I think), I've created the VLANs, setup their interface IPs, enabled the 3560 for routing and not i'm stuck on the trunks and how it should all fit together.

Cheers all for any help
0
Hi All,

I need some assistance setting up the below. I've got 3 "subnets" to set up internally. All must be able to reach the internet through the suppliers router.

The networks are 2x /26 and 1x /27. VLANS 601 & 603 are desktop pc's. VLAN 602 will be Cisco phones. 601 and 603 do not need any seperation, they're just to cover the seperate DHCP ranges. DHCP will be provided by an external source (hopefully) through a VPN setup on the ASA Firewall. I'm looking to setup outside interface, inside interface and access for all vlans.

Is anyone able to provide a sample config on how I could get this working?

Network Overview
Thanks,

J
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Hi
ive never achieved the following, id like to add a switch to our network that it some meters away.  How best to achieve this?
we are looking at https://h20195.www2.hpe.com/v2/getpdf.aspx/c04111401.pdf
thanks
0
Shoretel and switch STP on/off?

Hi

Looking at replacing our switches from procurve to Aruba.   Changing the method from daisy chained via ports to a stacked method using same models.  

Im unsure if we need to have STP disabled for shoretel to function?  If this is the case we cannot stack, which i find odd.

Thanks
0
Can I configure NAT with Static Route ?

This lab, is for Site to Site VPN, but I have used NAT with it. I used the example from this site:
http://www.mustbegeek.com/configure-site-to-site-ipsec-vpn-tunnel-in-cisco-ios-router/


In the configuration below, I have configured static routes for end to end reachability, and it is working fine. however I am not sure about NAT. when I run : R1#sh ip nat translations
 on R1 or R2, it does not show anything translated after I ping from R3 to R4 or vice-versa.

Any idea ?

Thank you
n


R1#show run
Building configuration...

Current configuration : 2313 bytes
!
version 15.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
aqm-register-fnf
!
!
no aaa new-model
clock timezone CET 1 0
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!         
!
!
!
!


!
!
!
!
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!         
redundancy
!
!
! 
!
!
!
!
crypto isakmp policy 5
 encr 3des
 authentication pre-share
 group 2
crypto isakmp key cisco@123 address 192.168.12.2   
!
!
crypto ipsec transform-set MY-SET esp-aes esp-md5-hmac 
 mode tunnel
!
!
!
crypto map IPSEC-SITE-TO-SITE-VPN 10 ipsec-isakmp 
 set peer 192.168.12.2
 set transform-set MY-SET 
 match address VPN-TRAFFIC
!
!
!
!
!
interface Ethernet0/0
 ip address 192.168.12.1 

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0
Hi
We are expanding our office so will need to install an additional switch in another room c20 feet away from the comms.  At the same time we are looking at replacing our existing switches.  

Currently have a hp 2910al poe+ 48 port serving as GW for hosts.  It routes to the local firewall and thereafter out tot he web via router.  We run two vlans for data and voice.  
We also have two other switches connected via ports on the 2910al.  These are HPv170 and 3com 2952, these run only data, no voice.

Looking for recommendations for specs and types of switches.  We like HP but would use any other.  Ideally have some form of resiliency and HA in the comms room and the same with the other switch in the other room.

Would modules be any good?

We also have STP disabled for our voice to work.

Thanks
0
Configuring NAT

in the LAB configuration below:
I have R1 and R2 in subnet 192.168.12.0/24 ----R3 in subnet 10.10.13.0/16  and R4 in subnet 10.10.24.0/16

I would like to have R3 be able to ping R4

The NAT configuration does not seem to work as it is supposed to.
Any Help ?

Thank you

n




R1#sh run 
Building configuration...

Current configuration : 2199 bytes
!
! Last configuration change at 02:39:42 CET Sun Sep 2 2018
!
version 15.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
aqm-register-fnf
!
!
no aaa new-model
clock timezone CET 1 0
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
!
!
!
!
!
!


!
!
!
!
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!         
!
!
redundancy
!
!
! 
!
!
!
!
crypto isakmp policy 5
 encr 3des
 authentication pre-share
 group 2
crypto isakmp key cisco@123 address 192.168.12.2   
!
!
crypto ipsec transform-set MY-SET esp-aes esp-md5-hmac 
 mode tunnel
!
!
!
crypto map IPSEC-SITE-TO-SITE-VPN 10 ipsec-isakmp 
 ! Incomplete
 set transform-set MY-SET 
 match address VPN-TRAFFIC
!
!
!
!
!
interface Ethernet0/0
 ip address 192.168.12.1 255.255.255.0
 crypto map IPSEC-SITE-TO-SITE-VPN
!
interface Ethernet0/1
 ip address 10.10.13.1 255.255.0.0
!
interface Ethernet0/2
 no ip address
 shutdown
!
interface Ethernet0/3
 no ip address
 shutdown

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0
I want to know if I can monitoring my Dell switches using MIBs as a custom device or using SNMP v2.

Found this guide

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/117707-config-ngwc-00.html#anc4

But I have read that even using open standards. Sometimes Cisco Prime couldn't recognise the device.

Any experience with Dell switches?
0

Switches / Hubs

21K

Solutions

17K

Contributors

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.