Questions tagged [switchport]
For questions about switchports on network devices. For instance, you want to configure a trunk on a router interface or you are wondering how you setup an interface on a switch for a server.
80 questions
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Switchport command to find out what ports aren't active on a switch
I know that sho int | inc connected shows connected ports. What do you use to find ports that aren't connected?
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IP Assignment for applying ACL on Cisco Nexus3500 C3548P-10GX Chassis
Context
Following are the details of the layer-3 switch
cisco Nexus3500 C3548P-10GX Chassis
Intel(R) Core(TM) i3- CPU @ 2.50GHz with 16396528 kB of memory.
Processor Board ID FOC25244X6C
We have ...
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90
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Cisco catalyst 3750 switch fault
Please I need any help or advice I can get. My switch was working fine all of a sudden the computers connected to the switch stop receiving connections. Upon checking the switch, I discovered all the ...
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Best Practices for Configuring Port Security on a Layer 2 Switch
How to configure port security on trunk and interfaces
I'm learning about port security and have a few questions. I have a layer 2 switch with interfaces f0/1-22 in access mode to access VLANs, ...
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501
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Deleting description on Cisco 9300 switch
I have a port that has a description that is not needed. How do I go about just deleting that line. Sorry for the simple questions, I am very new to the networking world.
interface GigabitEthernet3/0/...
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234
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Failover with sticky MAC address on network switch
Introduction:
I am configuring a server to have two ethernet ports (one as primary, the other is redundant) connected to two different switches. In the switches, I enabled the sticky MAC address and ...
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243
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Difficulties retrieving attached device MAC addresses from switches/switchports
We have hundreds of mostly Cisco switches and I'm trying to track down all the MAC addresses (latest would be good enough) seen by all the switchports. Following the suggestion given here, I've been ...
- 111
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DOT1X: A practical case for ForceUnauthorized state
I have been working as a Network Engineer for almost 5 years now. I have never encountered a scenario where I would need to configure a Cisco switch port as ForceUnauthorized (DOT1X).
According to the ...
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963
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Cisco Core Switches - Identifying unused ports
I've started at a new site, and the server room is an absolute state - I want to get in and start removing unused patch leads, so that I can start to see what is available & to tidy up.
There is ...
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3
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743
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Why switch uses Mac address during implementation of spanning tree protocol (STP)?
We know that layer2 switch doesn't use Mac address ,uses only certain port number to accept the frame.
But I have been read on book as well as internet that uses Mac address to find spanning tree for ...
- 406
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742
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Managed Switch, Setting up VLAN Tagged, Untagged, allowed & tagged only etc
Looking for some help setting up a Dell PowerConnect 2724. 1st time setting one of these up.
The best graphic I could find to explain my setup:
My router DHCP is enabled so it will provide IP ...
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How Can a VPC ping the Router through an Etherswitch that behaves in one port as router and in the other as switch
In the following topology my main purpose is to:
1)PC11 ping Router(R)
2)PC11 ping PC13
ESW10:
In gig0/3 has the no switchport command and a given IP address.
In gig0/2 it has the switchport access ...
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440
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Switch Port channel down but firewall did not log the port down event
Can some one help me here if I am missing anything to check.
Issue:
Our Palo Firewall got a vwire configured with interfaces eth1/5 & eth1/6.
eth1/5 is directly connected to eth1/2 of cisco switch ...
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266
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ARP isn't showing all the interfaces/MAC bindings
I'm playing with Dot1x port authentication, the interface G2/0/2 is connected to a PC and is authenticated/authorized successfully:
SW1-2960#show authentication sessions int g2/0/2 det
...
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56
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IPFIX vlanId element in access switchports
According to IANA definition, IPFIX elementId 58 vlanId is:
Virtual LAN identifier associated with ingress interface. For dot1q
vlans, see 243 dot1qVlanId.
But according to RFC5102:
Description:
...
- 113
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1k
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System default switchport shutdown on Arista EOS
Is there any equivalent to:
system default switchport shutdown
As available on Cisco's NX-OS to Arista EOS running with at least version 4.25.1F?
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448
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Using GNS3 to Sniffing Packets on Siemens RuggedCom RS900
I am using GNS3 to simulate an environment. I have 4 docker containers which all host Python programs. Three of the devices communicate with each other via the programs (Program 1, Program 2, Program ...
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512
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In RSTP, where all switches generate their own BPDUs, are they limited to forwarding them only on designated ports? (like in classic STP)
I recently learnt a rule in STP: only Designated ports forward BPDUs.
However, I'm not sure about this in RSTP since ALL switches generate their own BPDUs every few seconds. So, in a certain LAN ...
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319
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VLAN not working in ComNet switch [closed]
I'm trying to configure VLANs with 3 switches ComNet (2- CNGE2FE8MSPOE + 1- CWGE26FX2TX24MSPOE) and it's not working as I expect. It's the first time that I work with VLAN and I don't know If I didn'...
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Do X.25/Frame Relay/ATM/MPLS have their own switches?
In the context of networking when we say "switch" we always think of Ethernet switch.
But do we have X.25 switch, Frame Relay switch, ATM switch, and MPLS switch?
If yes, how are they ...
- 521
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377
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Propagating Static MAC Addresses
I have a situation where I need to place a static MAC on a switch as the server in question does not generate any outbound traffic. This static MAC seems as if it will work for hosts on the same ...
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431
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Huawei switch mac address sticky (model S5720) persistence after power cycle
Suppose I configure the commands "port-security enable, port-security mac-address sticky" in a Huawei switch port, then an endpoint device is connected on the switch port, and a MAC address ...
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107
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Show ports in use on Catalyst 3570
I picked up a used C3570 and am new to IOS. I am trying to ask the switch to show which ports are in use. My searches lead to the command "show modules" but that's refused by the switch (...
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Can use virtual port as the port mirroring's destination port?
Port mirroring can mirror several source port to a destination port(mirroring port).
I have several questions about port mirroring.
in the dest port, how to differentiate the different source port? ...
- 1,787
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822
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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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2k
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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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2
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1k
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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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416
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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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Packet Processing Limitation of OpenFlow Pipeline in Hardware Switches
I have a 10Gbps network containing 2 servers (DellPowerEdge 4700r) and a hardware switch ( ARUBA 2930F) in between. The two servers are connected via 10G SFP+ ports to the switch. I send TCP traffic ...
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3
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How to find out which port is located on a switch physically
I'm trying to physically located a port on a switch. I know which port the mac address is connected to. The port is Gi2/0/14. But this is part of a stack. How do I know which switch this port belongs ...
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231
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What are network port maps and what are they used for by the networking team in an organization?
I am curious to know what information generally the port maps contain.
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dhcp client not receving the ip address using two switches
1) In Router 4(R4)
i have configured the 2 dhcp pool. first dhcp pool with ip address 150.10.10.0/24 and second one with 150.20.10.1/24 in subinterfaces f0/0.1 and f0/0.2 and encapsulated using (R4(...
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Connecting DELL N1548 to HP Core switch with LAN
I currently have a setup with a HP core switch with few VLANs configured on it e.g. vlan 10, 20, 30, 40.
However when I uplink my DELL N1548 to the HP core switch, I cannot connect anything behind ...
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Are there any of NX-OS switchport "meta tags" alike features?
I believe I once stumbled across an NX-OS feature which we currently need, but for the sake of it, I can't remember the details like platform (100V, 5000, 7000) or version. We are currently using 5600'...
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Why Access ports should have the same trunk native vlan? [closed]
In the current switch Management VLAN is 48. Can you please someone explain it to me, why we dont give trunk native VLAN as 48, and we configure the same as access VLAN?
Thanks in advance.
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Why STP has to be disable on Trunk Ports?
I have 5 Switches on a Private Network 10.0.0.0/8 with 8 Vlans. On Access ports is running Rapid STP. On Trunk Ports between Switches should i disable STP or not?
I would be very pleased if someone ...
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543
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Port Channel Hybrid Port Issue
I have a Dell Sonicwall NSA 4600 running the latest firmware with an Interface that's configured to have a secondary redundant port. This interface also has a VLAN sub interface assigned to it.
On ...
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JunOS, access mode interface asks for a vlan
I'm kinda new to networking so I'm going to do my best to try explain my issue.
The issue that I have is that I want to delete all default configuration for my xe interface.
Current configuration:
...
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Best Practice for Voice and Data VLAN on single port
We have multiple interfaces currently configured with the below on our Cisco 3750x switch.
interface GigabitEthernet1/0/21
switchport access vlan 4
switchport trunk encapsulation dot1q
switchport ...
- 681
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Does the dot3StatsInternalMacReceiveErrors counter include Vlan mismatches
I am wondering if the dot3StatsInternalMacReceiveErrors counter includes VLAN mismatches, i.e. Discards due to VLAN mismatch. http://oid-info.com/get/1.3.6.1.2.1.10.7.2.1.16 only explicitly lists ...
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What's the `line protocol` and `Link`?
When I show a switch interface information, there are line protocol and Link:
Switch-A(config-if)# show interface gigabitethernet 0/3
Gi0/3 up, line protocol is up (connected)
Bridge Port Type: ...
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Obtaining packet switch-port information via a mirrored port?
When sampling a mirrored port of a switch, is there any means of determining the switch-port information of the packet?
Since Ethernet packets do not contain this information, I assume the answer is ...
- 169
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HP switch "No untagged port"
A network engineer showed me the show vlan output of an HP switch. I know tagged ports are trunk and untagged ports are access in Cisco terms. But can anyone explain the "no untagged port"? How is ...
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217
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Switch syntax, vlanXX and vlan [space] XX
How does a switch OS know that this is the same syntax? There are certain commands where you might reference the vlan like so "switchport access vlan 35", (a space between vlan and the number) and ...
- 101
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848
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MAC Address learning process
Does a switch learns hosts mac address in these following scenarios:
Switch port configured as access and frames received tagged on different VLAN
Switch port configured as trunk and frames received ...
- 1,085
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282
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Block internet on a Cisco catalyst 3560 port
Good day
Is there a way to block a specific port in a Cisco Catalyst 3560 switch to block the user from accessing the internet but still have full access to the internal corporate resources. The ...
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694
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The Egress to switch port is direction a or direction b?
I have a doubt about the switch port Egress direction and Ingress direction.
you see the upper have Egress rate limit.
I want to know the Egress to switch port is direction a or direction b?
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When are Native VLANs used? Are there times when a Native VLAN will never be used?
This is probably a simple one, but I am very new to VLANs.
I'd like to avoid using VLAN 1 as well as gain a better understanding of when native VLANs come into play when setting up a switch.
On ...
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When the data pass the Switch in port can represent cost value?
The snapshot is a tutorial of Switch.
You see the bellow snapshot, from the ROOT SW1 node to SW3, there are two path:
the author says the the path1(left side path) cost is 0 + SW3-in-port. the path2(...
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How can I config multi switch port efficiently?
I have a Cisco 2960-24TT Switch, no I want to shutdown all the switch port, I have to enter the interface then execute no shutdown and exit it then re-do this steps.
how can I config multi switch port ...
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