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6

You have to already have a VLAN in the allowed list (not "all") before you can use the add command to append to the existing list. So, first, use: switchport trunk allowed vlan 52 Then you can use: switchport trunk allowed vlan add 160,176,177,247 The reason being, right now it's set to "all", so there's nothing to add since they're all ...


6

The problem is not the traffic from the server to the switch, but the return traffic, from the switch to the server. Since the VLAN is native, the switch will sent the traffic for this VLAN untagged, while the server expect it tagged. So this cannot work as is. You should probably use this VLAN only for PXE boot and configure your server Operating ...


5

Yes. You don’t even need a trunk. If all ports on both switches are access ports on Vlan 3, then the port connecting the two switches are on Vlan 3 and both switches form one broadcast domain on that Vlan. If switches are unmanaged then all ports would be on the one Vlan and the number is irrelevant. A couple helpful details: Access ports to end hosts or ...


4

Without VLANs, connected switches form a single broadcast domain - that is exactly what you need for an IP subnet. Just connect away. VLANs allow you to split (partition) a shared switched infrastructure into distinct broadcast domains - ideally suited for multiple IP subnets. In order to connect multiple VLANs across a single link you'd need a trunk, ...


3

Vtp pruning is used in network for reduced unwanted brocast traffic of vlans . Only choosen vlan brocast traffic will be allowed into choosen links .so that network bandwidth is optimised..and there will be no latency in network.


3

switchport trunk allowed vlan all might be the way forward to get from a restricted 802.1q trunk to an unrestricted one ("unrestriced" as in: all VLANs allowed), without having to worry about some vlans being removed temporarily. Reference: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus7000/sw/interfaces/command/...


3

The PC knows nothing about VLAN, so when it sends a frame, it is an untagged one. Since the port has "native VLAN 1" when an untagged frame enter the port, it is associated with VLAN 1. If VLAN 1 is not in the list in the allowed VLAN, it is dropped. So when you add VLAN 1 in the allowed VLAN, you allow the frame to goes in.


3

The instructions are ambiguous. Once the port is configured as a trunk, any access configuration statements are meaningless. If they want you to remove the now vestigial access mode configuration, that's what they should ask you to do. I would recommend getting in the habit of removing the access mode configuration(s) for trunk ports as a "Best Practice" to ...


3

no switchport access vlan is used to reset the access-mode VLAN to the appropriate default VLAN for the switch. This default vlan can be defined by the administrator to be any value(which means it could be other than 1). Keep in mind that the concept of 802.1q tagging makes no sense for an access port. switchport trunk allowed vlan remove 2-4094 allows ...


2

Its fixed, for everyone who is curious to the issue... After 3 days of testing and experimenting i found out that one of the cables is not 100%. After putting a new cable between PfSense and the switch everything works with the configuration like described in my question.


2

A stack of 2 switches forms a single logical switch. So you first configure the stack, without considering the third one. You now have 2 switches (one stack and one standalone) Then you create a Ling Aggregation Group (LAG) between the stack and the third switch, with a link from each stack member to the standalone switch. Note: HP use the term "trunk&...


2

Before there was 802.1Q trunking, Cisco came up with ISL trunking. The IEEE bowed to the other industry vendors and came up with 802.1Q. Cisco added that to its repertoire, and the switches required you to choose one or the other. Cisco deprecated ISL, and the modern Cisco access switches only do 802.1Q. The Cisco distribution switches and routers still ...


2

The switchport trunk encapsulation dot1q command tells the switch that the interface should use IEEE 802.1Q encapsulation on the frames when the interface is configured as a trunk. Basically 802.1Q inserts a VLAN tag on the frames. This contrasts with ISL that actually encapsulates the frames with an ISL frame. Many newer Cisco switches have dropped support ...


2

Why does a chain of switches having proper trunk configuration between them DROP packets? It doesn't unless there's congestion, or the trunk configuration is not proper. In your case the key is "the active VLAN interface is not up". Depending on the exact behavior of the switch, either all interfaces associated with the VLAN are down or the VLAN itself is ...


1

That is not actual stacking, where multiple switches look like a single switch for management and configurations. What you seem to want is to create a LAG (Link Aggregation Group) between two switches. I believe you can do that with LACP on those switches: trunk ethernet <range_of_ports> trk<trunk_number> lacp Keep in mind that a single flow ...


1

You do not have EIGRP enabled on your (layer 3) switch, so the router and other devices don't know how to reach the networks on the switch. And BTW, you are not trunking VLANs. The VLANs terminate on the switch. Port 1/0/24 is a routed interface, not a trunk port.


1

As per your requirement you have two options .Again this two options have they own dependencies to fullfill requirements Option 1 : Two connect all computers and serves within single subnet . But to make it possible you need to change ip address of network B or network A to make it same subnet .. so that computers and servers will talk to each other in ...


1

Routers route between networks/subnets. A layer-3 switch makes a fine router for this purpose. In my understanding of VLANs, it should now be possible for both computers to talk to the server but they should still be on Network B. This way, no routing would be needed because communication flows on OSI layer 2. Whether you use VLANs to actually separate the ...


1

your topology seems to be incorrect servers should not Connect with router interfaces. your requirement can be optimized by replacing router with layer 3 switch with possible SVI switch Virtual Interface configuration with VLAN 10 ,VLAN 20 ,VLAN 30 please try with below topology Network Diagram


1

The problem is that all the interfaces in slot 2 (G2/1-2 and F2/3-2) of the router are switch interfaces, and you are trying to use them as router interfaces, but that will not work. What you need to do for those interfaces is to create SVIs for the various VLANs, then assign the switch interfaces to specific VLANs as access interfaces or as trunk interfaces....


1

The default VLAN in a switch is the one applied to ports when their configuration is reset, for instance when you remove a port from a LAG trunk, or a new port module is inserted in a chassis. The native VLAN of a trunk port is the one that is forwarded and accepted without tag. Often, a VLAN trunk port has all VLANs tagged.


1

Whenever you want to use VLANs, make sure that the VLANs were created on the switches that use those VLANs. You can look at the VLAN database (vlan.dat file) to make sure. If you use VTP, it may spread the created VLANs to all the switches, but VTP is sometimes problematic, and it can be a security risk, so a best practice is to set the VTP to Transparent ...


1

Vlan allowed features allow us to allows only specific Vlans which we are specifying on trunk port . **For example ** Switch (config)#int f0/1 Switch(config)#switchport mode trunk Switch(config)Switchport trunk allowed vlan 10,20,30 Switch(config)#no shutdown Allowing specifically Vlan is good practice instead of allowing all vlans because network is ...


1

No need to create sub interface with public ip . You need to assign public ip for outside interface of router . Ànd do natting nat overload Router(config) # access-list 1 permit ip 10.0.0.0 any IP NAT inside source list 1 interface "router outside interface" overload IP route 0.0.0.0 0.0.0.0 point towards gateway of ISP


1

try to optimize your nat translation by nat timeout ip nat translation timeout 300 ip nat translation tcp-timeout 180 ip nat translation udp-timeout 120 ip nat translation finrst-timeout 30 ip nat translation syn-timeout 30 ip nat translation dns-timeout 30 ip nat translation icmp-timeout 120


1

On the ESXi side, assign a VLAN ID to the port group you want tagged. A port group without VLAN ID goes untagged. On the physical switch side, create a trunk and assign VLANs as tagged and untagged as required (max. 1 VLAN untagged).


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