Questions tagged [subnet]
Questions relating to IP subnetting, including planning, calculation and best practices.
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Switch ping to router with trunk port
If I have a switch port trunk directly connect to a router with the follow scenario below:
-------- g1/0/1 (Trunk) g1/0/1 |------|
|switch| Native VLAN 1 SVI=...
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Wrong subnet configuration works anyway in a shared bus, but doesn't work in switched lan. Why?
I was told that this configuration (which contains an error in DNS mask which is /23 instead of /24) works only because it's a SHARED bus. If it was a SWITCHED lan, the DNS responses from DNS to A ...
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about subnetting ip adress 172.16.0.0 [duplicate]
can you explain why we have 172.16.0.0 to 172.31.0.0 so it can't be for example 172.13.0.0 to 172.35.0.0.
And also why is 192.168.0.0 and is it possible to be 192.160.0.0? thank you
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Outgrowing a /24 network
We have outgrown our 192.168.1.0/24 network. We are ready to replace the router so I thought this would be a good time to expand the network. I've configured plenty of /24 networks but never anything ...
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Connecting and combining 2 networks
I have networks in 2 separate buildings. Each has its own private IP range. We're installing a private fiber link between the two buildings. Do I just need to adjust the subnet mask so they can see ...
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Communicating to a device with a random IP, Subnet Mask and Gateway
I think am looking for a way to reliably communicate with devices connected to the network with "wrong" configurations.
Our company sells products that can have their network settings ...
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2
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81
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Communication with different subnet masks
So I try to explain the dilemma.
I have 2 groups of clients and one server.
I want these groups to only communicate with the server.
This means that each device in these groups should see the server, ...
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Is internal network traffic sent to private subnets via their NAT Server?
Similar to this question, I'm wondering how resources in my public subnets communicate with those in my private subnets - when there is a NAT service present.
My impression is that a self-managed NAT ...
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RIP v2 Network Command
I am comparing the Boson ExSim Lab to the Neil Anderson's Lab on RIP.
On one of the labs on Boson ExSim, it asks to configure RIP on the routers, all of which are on some form of a 192.168..0.0/24 ...
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Alternative to the Internet for a local network
Suppose we are designing a network and we want to isolate it from the Internet. Are there any alternatives to the Internet for a local network?
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How do you create multiple classless networks out of single IPs, then divide them into networks and subnets? [duplicate]
I'm having trouble figuring out how to create 4 classless networks out of 10.0.0.0/24, then dividing it into 4 equal subnets.
I'm also not sure how to create 5 classless networks out of 20.4.3.8/16, ...
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If all subnets are a part of same vlan, then the network segregation using subnets does not make sense
This is what we know about subnetting.
By dividing a network into subnets, you can separate different departments, locations, or security zones, creating distinct broadcast domains. This segmentation ...
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Access multiple networks via one managed switch
We have a kind of granulated network structure. At the moment I have two network adapter connected to my system for two of the network areas. The Systems in network A and network B should not ...
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Reach IP in a different subnet
I have two Ethernet devices:
One is 10.1.1.10 with a netmask set to 255.0.0.0
The other is 10.255.253.5 with a netmask set to 255.255.255.0
Why can't I reach the second device from the first one (...
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Is it a thing to subnet an address but still use initial network host?
Hei,
Suppose we have 192.168.0.0/24 and we subnet it as 192.168.0.0/25. Is it a normal thing to configure hosts with IP addresses in both /24 and /25 address spaces ? We consider /24 and /25 to be in ...
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Use a single FortiSwitch in multiple, segmented networks
Is it possible to use a single switch in multiple, segmented and firewall protected subnets?
Looking at the above picture, I have this existing network WITHOUT the two inner firewalls. The switch is ...
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Is is possible to create a network using supernetting like this? [duplicate]
I need to create a network in the range 200.1.x.x and split it into 3 LANs which consist of 1250, 1750, and 1500 hosts respectively. This network should be able to expand to a total of 56 networks. ...
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How does subnetting solve the problem of IPv4 address shortage?
Reading articles on the web, they all say that "subnetting solves the problem of IPv4 address shortage by dividing a large physical network into multiple smaller networks". I do not ...
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Not able to ping device with different subnet on gateway and ip adress
I am trying to ping a device with IP 192.168.0.200, subnet mask 255.255.255.0. It is configured with gateway adress 192.168.1.1.
Is it because the gateway subnet, and ip adress subnet is different i ...
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I am getting Confused with host bits and Subnet bits [duplicate]
So i am playing with Cisco CML. I made up a random address 3.0.0.0/8.
I wanted to split up that subnet into 4 subnets, So 2^2 = 4. I kinda got confused along the way. In my train of though if we use ...
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GNS3 subnetting and routing
I have a project assignment that consists of 3 routers, the ISP, and 2 company routers, the ISP can address a network /24 IPv4.
I delegated a /25 to DNS servers and a /26 to one company and 2*/30 to ...
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Make printer in different subnet accessible to other subnet
i am creating a network and i want the printer which is in a different subnet to be accessible by all other subnets. The router network is 192.168.10.0/24 further subdivided into /28 subnets.
The ...
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Is there any point to learning about old network address classes anymore? [closed]
It's 2023 and I continue to see people write about IPv4 A,B,C,D, and E networking classes like they still mean something and without saying it's only mentioned for historical purposes. But they are ...
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The use of a link local IPv6 address
In a networking course that I'm following, there was a mention of several ways of how IPv6 link local addresses can be used, such as
Assigning the link local address of a router/L3 switch as the ...
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What are all the reasons for using a separate /31 subnet for a p2p link?
For example in this LAN, the 13.65 and 13.66 are a separate subnet between slip and bsdi, but what is the reason that they have a separate subnet?
The only reason i can think of is that bsdi cant have ...
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Question, provisioning divisions of network blocks with differing sizes based on number of hosts required [duplicate]
I was working on this question.
To do this question I used this YT video to help me and I came up with these answers but I wasn't sure about them since there are no answers to the practice questions.
...
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Server with multiple NICs takes different route when answering
I have multiple servers which share 2 networks.
That is the LAN Network at 192.168.1.0/24,
aswell as the Backbone Network at 192.168.5.0/24.
┌────────────────┐
...
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How do devices on a network communicate when they are only connected through a router? [duplicate]
This is in my router's routing table:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 ...
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Variable Length Subnet Mask with two hosts [duplicate]
I started learning subnetting and i encountered some problem involving Variable Length Subnet Mask and which problems i encountered so far is it just specify a specific number of host per subnet but ...
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Mask for sending network packets
When sending packets in a network, do the PC's all have to share the same subnet mask or can you dedicate comps to mask addresses? I am wondering if this also determines collisions and if it is a ...
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Routing question
Let’s say I have router A and B and a subnet 192.168.10.0/24. Can I use part of that subnet as a connector between router A and router B (ie. 192.168.10.0/30, .1 on A and .2 on B) and have a route 192....
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What is the Logic of AND and OR operations in subnetting?
To calculate subnetting for given IP address and the subnet address, we do AND operation first to get the network address and the first usable IP address of the subnet. Why do we use AND? I know it ...
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While VLSM subnetting, will there be a case that addresses are insufficient? [duplicate]
Note-:Here, IP address means IP address+subnet mask.
I am studying network design. My question is will there be a moment where you choose IP address for subnetting but turns out finally that it's ...
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IPv6 subnets without delegated prefix
I have received an IPv6 network from my provider, say it's 2001:db8:1::/48.
I did not get delegated prefix from them.
I would like to use the IPv6 addresses on different networks behind a firewall (...
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What would be the correct way to go about subnetting an IP address for two networks? [duplicate]
I am struggling with how to proceed with this. I have started by converting the IP address into binary. If somebody could just give me a push in the right direction I would appreciate it!
There are ...
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Why shortened version of IP4 exists and it is undocumented but supported everywhere?
For example there is an IP address 192.168.0.1
It is clear that you can use it as the full line, but try that one 192.168.1
It will also work, and it will be automatically converted to 192.168.0.1
...
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Why should I use vlans instead of subnets?
I know that this might be a trivial question for the more experienced. However, I am a student who has just started designing networks.
Assuming you have to design a network of a school divided into ...
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How to create a subnet or secondary network? Do I need VLANs?
I am not new to IT, but in the past, I've always had a Network Admin to handle this type of stuff. That being said I know just enough to be dangerous.
What I have is an old hodgepodge of different ...
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Why is this 254.63.0.1, not a valid host address?
Getting the below error, when trying to configure the ip address 254.63.0.1 as an SVI.
Switch(config)#interface vlan 254
Switch(config-if)#ip address 254.63.0.1 255.255.0.0
Not a valid host address -...
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How to redirect traffic when one site goes down without downtime and the subnets are different?
We have a uniform high availability configuration [somewhat like 1] with the difference we have two different subnets, vlan and vsphere for two different sites, X and Y. The host in site X has ip 10....
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ARP requests from a different subnet
Not sure if my question is on-topic here. I found the following question about ARP requests from a different subnet and I was wondering if and when this is an actual use case. The original question is ...
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How is CIDR used in ranges?
There are times where CIDR notation isn't used to subnetting or for routing/summarization but rather just for ranging IP addresses, IPv4 mostly. It seems very non-standard and it seems to be like a ...
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why ip adresses are divided into network portion and host portion when we already have NAT [duplicate]
I don't understand why ip adresses are divided into network portion and host portion? is the host portion really necessary when we already have NAT?
for example, if ip addresses only have network ...
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Do the subnets x.x.x.128/25 and x.x.x.192/26 collide? Why or why not? [duplicate]
I am working with a vpc cidr of /23, and need to divvy up some public and private subnets for hosts, load balancers availability zones etc. please bear with this newbie question
Please assume I am ...
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Can networks with different netmasks overlap?
Let it be this diagram:
Can I assign such networks at each segment without overlapping? In my understanding each network has a range of usable IPs and those ranges overlapps each other.
For instance, ...
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Why would we want to subnet/change CIDR of private addresses?
I am studying for my CCNA and my current topic is subnetting.
I understand how subnetting works and how to subnet (calculate the network IP, the amount of hosts, broadcast, etc). However, I can't seem ...
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Routing for same subnets in remote sites
Is it possible to have interVLAN routing with router on a stick topology, but with remote sites communicating via OSPF? In the diagram below, I can ping PC1 from PC0. What I want is to ping PC2 and ...
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Same subnet on multiple VPN clients
I have an openVPN server, where multiple clients are connected.
These clients are usually routers, so they have a subnet behind these routers.
I want to access all clients on these subnets if I ...
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Dividing a network into subnets using a router
I am learning about how L3 and IPv4 addressing works and I need some clarity on certain things.
I've encountered the following topology
So in this topology, the router stands in the center and ...
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Subnetting an network into different number of subnets [duplicate]
Assuming you are using a Class C IP address (195.16.1.0) and you need to create the following numbers of subnets for your network plan. For each of the numbers of required subnets below, provide how ...
