5
votes
If all subnets are a part of same vlan, then the network segregation using subnets does not make sense
So, does Vlan and Subnetting go hand in hand? What I meant is, if we need to use subnetting, the do we need to also make sure each subnet is part of a different vlan?
In 98% of the cases, YES. You ...
- 67.5k
4
votes
Non VLAN Tagged Traffic Not Going Through Trunk Between Cisco Switches
You set the interface native (untagged) VLAN to VLAN ID 1 and then only allowed VLAN 79 on the Trunk interface so untagged packets (VLAN 1) cannot pass over it. Add VLAN 1 to the allowed VLAN list on ...
- 2,246
4
votes
Can we have two logging source-interface configured on Cisco Switch?
No. You can have only one source interface statement. If you try to add the second, it will simply overwrite the first.
- 67.5k
4
votes
Accepted
Cisco interface vlan (shutdown vs no ip address)
IPv4 is not the only layer-3 protocol. We have IPv6, and Cisco has supported others, too.
You could, for example, have something like this:
interface Vlan10
no ip address
ipv6 address 2001:db8:1234:...
- 99.6k
4
votes
Why does this access list block DHCP request?
DHCP Discover broadcast has to be whitelisted explicitly
ip access-list extended MITARBEITER
permit udp host 0.0.0.0 eq bootpc host 255.255.255.255 eq bootps
permit TCP 10.15.240.0 0.0.0.255 any
...
- 305
3
votes
Understanding VLAN Tagging for Network Segmentation
VLAN tagging is a way to label network traffic so switches can identify which Virtual Local Area Network (VLAN) a packet belongs to. It's crucial for network segmentation, improving security, and ...
- 31
3
votes
Accepted
HSRP and DHCP problem
You haven't mentioned the equipment in use and you have not said clearly that the layer 3 switch is acting as the DHCP server but you seem to indicate that is the case.
I can be pretty sure that in ...
- 2,246
3
votes
Accepted
Give internet access with a not VLAN enabled router to two VLAN networks
Connecting a VLAN to a device without tagging support requires a dedicated, untagged port ("access").
In reverse, a device without VLAN support can only use a single, untagged VLAN on each ...
- 84.4k
2
votes
Accepted
Trying to achieve ECHO request reaching destination in other VLAN
It's almost impossible to tell without information such as VLAN and spanning tree status information on each switch, etc. but I would guess from a quick glance that you have problems between the ...
- 2,246
2
votes
Trying to achieve ECHO request reaching destination in other VLAN
The VLANs need to be created on the L3 switch.
The gateway IP addresses must be configured on the L3 switch, on each VLAN interface/SVI.
IP addresses on an L2 switch are for management only - usually ...
- 84.4k
2
votes
Accepted
Layer 3 Switch IP Problem on Packet Tracer
You have the same IP addresses on both switches. This is an invalid configuration. Each interface needs a unique IP address. If you need one gateway address for your devices, consider using a First ...
- 67.5k
2
votes
Accepted
If all subnets are a part of same vlan, then the network segregation using subnets does not make sense
if all the subnets are part of the same Vlan, does the above advantage still make sense?
Not really. If there's no L2 segregation by VLANs (or separate switches) then any host can join any subnet ...
- 84.4k
2
votes
How does L2 switch forward tagged VLAN?
how does the L2 switch determine that the incoming tagged vlan80 packet should be forwarded to the L3 switch in building B?
Based on your description, interface GigabitEthernet2/3/0/47 is an access ...
- 67.5k
2
votes
Accepted
ASA5555-X vlans through port channel not working
I got this to work. All I had to do was restart the ASA after which it got the ip from isp dhcp... Then I had to fix the port channel config on the untagged lan part after figuring out that I need to ...
2
votes
VTP transparent mode Switch does not pass user traffic to and from other VTP Switches
This has nothing to do with VTP.
If Switch C only has VLAN 1, it's not going to forward other tagged traffic from one port to another.
- 67.5k
2
votes
Access list and interface vlan
I can confirm that the ACL is functioning as expected. Initially, I attempted to ping from the IP address of the Interface VLAN 13 (the gatway of this vlan 13) which means the ping was generated ...
- 41
1
vote
Accepted
Cisco 3650 and wifi hotspot
Found what was th issue.
I had to put native VLAN to all trunks between switches concerned.
- 11
1
vote
Accepted
Why is inter-VLAN communication not working in my network set-up in Cisco Packet Tracer?
First, you must create both VLANs on both switches, not just VLAN 10 on Switch 1 and VLAN 20 on Switch 2, but both VLANs on both switches:
vlan 10
name Switch_1_VLAN
!
vlan 20
name Switch_2_VLAN
!
...
- 99.6k
1
vote
Why is inter-VLAN communication not working in my network set-up in Cisco Packet Tracer?
First checks with VLAN-related problems:
Have the VLANs been properly created on all switches? Assigning them without explicitly creating them (VLAN xx↵) doesn't always work.
Can each node ping its ...
- 84.4k
1
vote
Accepted
VXLAN VNI VLAN mapping
802.1Q or QinQ tag, they don't tunnel.
VXLAN tunnels MAC frames over UDP/IP (layer 4) between two endpoints (VTEPs), including a 24-bit VNID VLAN tag. You can usually map QinQ tags to VNIDs.
The VTEP ...
- 84.4k
1
vote
Accepted
Switch ping to router with trunk port
Your diagram is a bit unclear, but let's try.
tagged VLAN 2 SVI=192.168.2.1 =trunk= Secondary IP=192.168.2.254
A secondary address on the router's native interface doesn't work. The router needs to ...
- 84.4k
1
vote
Accepted
Configuring multiple public IPs in Cisco 881 to forward private IPs with tags while bandwidth balancing
Is there a way to forward the private IPs with the tag (VLAN 30) to the switch
You can use an access port on the switch with VLAN 30 untagged, or a trunk port on the switch with a VLAN subinterface ...
- 84.4k
1
vote
Connecting a hub to my switch bypasses RADIUS/802.1X
That (trivial) MITM scenario is a well known weakness of 802.1X. It's also possible to use a simple switch in place of the hub.
That weakness needs to be addressed on the authenticating switch. You ...
- 84.4k
1
vote
Understanding VLAN Tagging for Network Segmentation
VLANs logically divide switches into separate, unconnected switches. Frames in one VLAN cannot be sent to an interface for a different VLAN. In order to connect to a device that communicates with ...
- 99.6k
1
vote
If all subnets are a part of same vlan, then the network segregation using subnets does not make sense
Agreed with what was stated above, using different subnet ranges in the same VLAN is unconventional - typically you'll want a subnet per VLAN. If you think about it VLAN is a 'virtual LAN' - at the ...
- 66
1
vote
Can we have two logging source-interface configured on Cisco Switch?
While Ron is right with the single source interface statement, depending on the network environment, you might be able to pull off a trick.
Still, whichever way you'll turn this, it's going to be very ...
- 8,836
1
vote
How does L2 switch forward tagged VLAN?
The basics:
Each VLAN acts like a separate switch.
A frame is associated with a VLAN on ingress - untagged on an access port or tagged on a trunk port. It keeps that VLAN association until it leaves ...
- 84.4k
1
vote
Accepted
Cannot enable link. Why?
After some experimentation I realized the problem was the "sticky" keyword line in the switch configuration.
If the sticky keyword is used, as in the second last line, the switch learns the ...
- 305
1
vote
what's the difference between tag-based and Port-based VLAN and which one is better?
Using VLANs, you can split or partition a physical switch into multiple, logical ones - each VLAN represents its own, closed broadcast domain and switching/bridging is only performed within that VLAN.
...
- 84.4k
1
vote
what's the difference between tag-based and Port-based VLAN and which one is better?
In this context the tag-based VLANs appear to be the standard implementation of the VLANs which conforms to the IEEE 802.1Q standard whereby traffic can be segregated to multiple virtual broadcast ...
- 113
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