Questions tagged [subnet]

Questions relating to IP subnetting, including planning, calculation and best practices.

Filter by
Sorted by
Tagged with
0 votes
0 answers
4 views

hi I had a question regarding public IP on cloud VMs [closed]

I was exited to create my first VM in the cloud (azure) and when I logged in I used the public IP , and when I created a webserver I refered back to the public IP. I was completyly shocked and ...
  • 1
0 votes
0 answers
18 views

Subnetting within an existing Production subnet [closed]

My company has a corporate-allotted /16 network where we can place any and all of our networked devices. I am inheriting this network, and would like to implement subnetting for security and all the ...
0 votes
1 answer
37 views

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....
  • 3
1 vote
1 answer
55 views

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 ...
0 votes
0 answers
7 views

How many number of bits and hosts? [duplicate]

If it's an IPv4 address and it's in the class B network. Iam supposed to make 20 subnets, what will be my number of bits to consider for the subnet and the number of hosts?
0 votes
1 answer
35 views

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 ...
1 vote
2 answers
95 views

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 (...
  • 111
0 votes
0 answers
12 views

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 ...
0 votes
0 answers
15 views

How many /56's are there in a /49 IPv6 [duplicate]

I am studying subnetting in IPv6. I came across the following question from a website called Subnetting Practice, which I will quote below. How many /56s are there in a /49? Could someone please ...
1 vote
2 answers
100 views

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 ...
  • 113
3 votes
5 answers
513 views

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 ...
  • 33
0 votes
1 answer
107 views

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 ...
  • 113
0 votes
1 answer
83 views

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 -...
0 votes
2 answers
55 views

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....
  • 3
0 votes
0 answers
7 views

Dividing network into subnets [duplicate]

My teacher uploaded this example question and solution as explanation of the topic: I watched some videos about it but none of them made it fully clear, what I don't understand here is: What are ...
0 votes
4 answers
225 views

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 ...
  • 163
2 votes
1 answer
38 views

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 ...
  • 73
0 votes
3 answers
75 views

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 ...
0 votes
1 answer
84 views

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 ...
1 vote
2 answers
68 views

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, ...
's user avatar
0 votes
2 answers
75 views

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 ...
  • 295
0 votes
0 answers
11 views

Subnetting and dividing networks [duplicate]

I am currently learning about how subnetting works and I need to get rid of some confusion. If we divide networks like this, and assign each network a different IP address (192.168.1.0, 192.168.2.0, ...
  • 295
0 votes
2 answers
86 views

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 ...
  • 11
0 votes
1 answer
103 views

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 ...
6 votes
5 answers
2k views

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 ...
  • 295
0 votes
0 answers
17 views

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 ...
0 votes
0 answers
29 views

is 10.10.153.0/16 v.s 10.10.0.0/16 the samething [duplicate]

I saw a confused subnet: 10.10.153.0/16, is it same as 10.10.0.0/16, or it should be 10.10.153.0/24. Thanks!
  • 317
0 votes
1 answer
110 views

Connect a router to multiple router/subnet - Cisco Packet Tracer

I'm studying DNS Server. So I try this. Here is the flow when I request abc.com webpage from My PC. My PC (192.0.1.2) send DNS query to Router0. Router0 then forwarding to DNS Nameserver (10.0.0.2). ...
0 votes
2 answers
138 views

Sharing one VLAN with two routers each one will route different subnet

We are transitioning to new WAN connectivity. I have one VLAN (let's say ID 10). Currently there is one router R1 that has one private subnet and one public subnet on the VLAN 10 which goes through ...
  • 3
0 votes
1 answer
83 views

Difference between network and sub-network

Today, at school I learned about subnetworks. So, let's say I have a 10.0.0.0 network with a 255.0.0.0 mask, I could subnet it into two networks, for example, 10.1.0.0 and 10.2.0.0, which would both ...
's user avatar
0 votes
1 answer
83 views

How can I test if the subnet mask and default gateway are set for a device? [closed]

I understand how subnet masks work mechanically and how to convert from the mask to the CIDR bits notation, and I understand the concept of a default gateway. What I don't understand is what setting ...
  • 101
2 votes
2 answers
64 views

Will 2 redundant Routers configured with HSRP consume 3 IP Adresses in each Subnet?

The Problem occured while studying for my exams Problem: I have to design a Network for a Company. The given IP Adress Space is 192.168.1.0/24 which has to be divided into 4 Subnets. These Subnets ...
1 vote
1 answer
65 views

What does an IP Address with CIDR represent precisely?

This question is more a question of definition then a technical one: You have some network with the network identifier 172.16.0.8 and a subnet mask 255.255.255.248 (/29) We know that the usable ...
0 votes
1 answer
130 views

Duplicate IP addresses on different "levels" of subnets

My question is quite simple: let us say there is a 10.0.0.0/8 with the subnet mask of 255.0.0.0 (first 8 bits used up for network address). Let us say, one address in our subnet is 10.0.0.1 (subnet ...
1 vote
5 answers
331 views

What happens to the unused IP addresses in the subnet that falls in between two routers?

This is probably a un-realistic question, but a question nonetheless, that has been bugging me since quite a while now. Consider the below network diagram, where R1 is a part of a 10.0.0.0/8 network (...
0 votes
1 answer
187 views

How to choose IP address and subnet mask while forming a network

This question is bit novice. But, just wanted to clear any doubts as a starter for this topic. I have read about Classes of address like Class A, B, C. As I observe the Default Subnet mask for each of ...
0 votes
1 answer
67 views

How can I set up two sub networks that can communicate by LAN but where only one has internet? [closed]

With only two routers, where one has a connection to the internet, is it possible to set up a second sub network that has no access to the internet, but where devices connected to either router can ...
  • 1
-1 votes
4 answers
119 views

Why isn’t there routing inside subnets?

As far as I know, inside subnets, there is no such thing as routing. How are IP-packets « routed » inside a subnet, and does this circumstance has an influence on how subnets are set up? Thank you in ...
0 votes
3 answers
98 views

If person A has a network 123.123.123 and person B has a network 123.123, what happens if they both assign an IP to a device of 123.123.123.123?

This is something I'm confused about...if person A and B have networks with different subnet masks, then what prevents them from assigning an end IP that is identical? It makes me think I'm ...
1 vote
0 answers
24 views

Personal VPN sub-network accessible through Work VPN? [closed]

I currently access my work network via Cisco VPN. At work, I have my own three computers and NAS on a personal dedicated router using my own DHCP. For several reasons, I do not want these computers to ...
  • 111
3 votes
1 answer
138 views

why can a router make two PCs in different subnets access each other?

Case 1: PC A: 192.168.1.2 / 24, and it connects to LAN port1 of router A PC B: 192.168.2.3 / 24, and it connects to LAN port2 of router A Given above we know A and B can't talk to each other due to ...
1 vote
3 answers
708 views

Router interface on same subnet

Could someone please explain why can't be have 2 interface on same subnet? Do router use network address to forward traffic?
  • 11
0 votes
0 answers
15 views

lan with multiple ip [duplicate]

If imagine lan assigned ip from from this range (192.168.1.0/24) then can we assign another ip from same subnet mask? If no why?
  • 11
2 votes
1 answer
51 views

Can wifi clients in same subnet talk to each other without a WAP?

I understand that a L2 device like WAP is needed to forward packets from one client to another within the same network (based on MAC mostly like in 802.11) However my question is, if there is no WAP ...
1 vote
1 answer
83 views

Must the host IP be contained in Router's subnet?

The settings are: manually set my host IP: 10.0.1.6/24, gateway: 10.0.0.138/24 they both know each other's MAC (arp -a shows the list) and there is a direct physical connection between them. From the ...
  • 11
0 votes
1 answer
35 views

Can an host on a subnet comunicate via an host on a segment of the subnet? and viceversa?

It's a theory only question. An host on 192.168.0.0/16 can comunicate with an host on the subnet 192.168.1.0/24 ? And viceversa? If no, why? NOTE: I already CAN calculate host, subnet, network id, ...
  • 103
0 votes
2 answers
69 views

Can two different LANs be part of the same private network? [duplicate]

If you had two geographically dispersed LANs with public IPs that are in a different subnet range to each other, (one is 154.30.24.x/24, and the other is 134.64.9.x/24) if they were physically or ...
  • 1
0 votes
0 answers
16 views

Do any subnets "Network ID" AKA "Network Address" always have an even number as the last octet? [duplicate]

Should a subnet have a "Network ID" AKA "Network Address" (eg: the first address, which is always unusable, and is the boundary between the previous subnet and the current subnet) ...
1 vote
2 answers
78 views

What's the different between a "mask" in route table and interface?

if we took Windows as an example, we can use the command "netstat -rn" to show route table as follows: IPv4 Route Table ===================================================================...
  • 113
0 votes
1 answer
73 views

What IP addresses are appropriate for a network inside an embedded device? [closed]

I am making an embedded device with two processors, a "gateway" processor which is connected to external ethernet, and a "webServer" processor, which is only connected to the ...

1
2 3 4 5
12