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5

For Communication between different subnets packet has to reach router or layer3 devices to process this packet . If another networks is directly connected then forwards packets on basis of ARP table . If destination is on another networks means forwards packet to next hops on basis of route entry Configured on network . However layer2 device cannot ...


5

Yes this is wasteful. The remaining IP addresses are lost. This is why we usually configure a /31 on such link. (Well actually if this /16 subnet is not announced to the other routers, technically it could be used somewhere else, but this would be a very dirty configuration).


4

Firstly your question itself is not providing required information to answer your query ! How your network topology seems to be .. Where your are creating a Vlans in router(inter-Vlan routing) or in layer3 switch (switch virtual interfàce). Usages of subnet pools is totally depends on your business requirements and how topology is designed. However your can ...


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Isn't it's range 10.0.15.15 to 10.0.15.30 which is within the VPC? Yes, but it's not a valid /28. 10.0.15.0/28 or 10.0.15.16/28 are valid ranges.


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RFC 6164, Using 127-Bit IPv6 Prefixes on Inter-Router Links explains that /127 networks are good for point-to-point links: Abstract On inter-router point-to-point links, it is useful, for security and other reasons, to use 127-bit IPv6 prefixes. Such a practice parallels the use of 31-bit prefixes in IPv4. This document specifies the motivation for, and ...


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That's sloppy writing in the instructions, but I'm pretty sure it means you should use /24 networks (i.e. 172.16.0.0/24, 172.16.1.0/24, 172.16.2.0/24, etc). It would've been better to say to use class-C-sized networks, but even that's obsolete terminology since network classes haven't been a thing since 1993.


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RIPE publishes a database indicating who is authorized to use address space. Other RIRs have similar databases. Outside entities also operate IRR databases for routing information. These systems are fragmented for historic reasons. When BGP-speaking ISP networks exchange routes, often, these routes are filtered using prefix-lists generated based on these ...


3

Routers need to have interfaces on a common subnet in your example. If the addresses you show are for the common link, they are not in the same subnet. You can either: Change router1's interface to 10.2.1.2/30, or Change router2's interface to 10.1.1.2/30


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The sub net A knows that the address of the interface of router A is its default gateway Default routes are configured on hosts, not subnets. It may be helpful to remember that a default route is just like any other route -- it just has the shortest mask. If you want one route to be the "secondary" route, you first need a mechanism for determining ...


3

If default gateway of clients is configured on switch . Then you can use another ip address to configure on interfaces connecting firewall and switch and ensure specific route Configured in firewall pointing towards. Switch ingress interface. default route need to configure on switch pointing towards ingress interfàce of firewall . But make sure your ...


3

It's not feasible to configure identicàl ipaddress in different subnets because ip conflict will occur . Routing issue will occur . But still you can use identical IP address in different subnets . if both are different networks in this scenario use source NAT IP addresss .so that orginal ip address is hided by nat translations to avoid ip conflicts .


3

Yes it's feasible for server to serve two different subnets This can be accomplished by Configuring two NIC cards , assign first NIC card with first choosen network subnet as fallow in network adapter properties settings. IP address Subnet mask Gateway Assign ip address and subnet mask for second NIC cards allowing not to configure default gateway. Further ...


3

R1(config-subif)#ip address 192.168.1.10 255.255.255.0 wasn't working while R1(config-subif)#ip address 192.168.1.1 255.255.255.0 was working. This should work . When creating sub interfàce with IPaddress 192.168.1.10 . This ip address act as default gateway for this Vlans . But make sure you assign another ip address to Pc ,assign 192.168.1.12 to PC0 .


3

Layer2 won't understand ip address , layer2 switch will only forward traffic on basis of mac-addres table Let have example Packet forwarding to host A from layer3 switch Once the packet reaches layer3 switch as host A as destination , layer3 devices process this packet by varyfying routing table , in routing table it found that this network was directly ...


3

General different VLANs won't communicate to each other. To ensure communication between different Vlans routing is required . . By configuring Inter-vlan routing among different VLANs in layer3 device . Different Vlans can communicate among them . When there is traffic between same Vlan host traffic will be forwarded on basis of destination mac address ...


3

Please ensure static routes are configured on all routers for reaching management IP address from each router . *In RouterR1 Router1(config)# destination 198.51.100.0 subnet 255.255.255.0 pointing towards gateway 10.0.0.2 Router(config)#destination 198.51.100.0 subnet 255.255.255.0 pointing towards gateway 10.0.0.6 In Router2 Router1(config)# destination ...


3

why can't we have 2 interface on same subnet? You can (some devices may see that differently though). There are just very few situations where that makes sense. A router forwards in between subnets, so multiple interfaces with the same subnet are rarely useful. (I'm referring to logical interfaces. Multiple physical interfaces commonly make sense when ...


3

I wonder since the packet still has its source IP as 192.168.2.3 and target IP as 192.168.1.2 which are of different subnet, when PC A receives the packet, it will still check the packet's source IP with 255.255.255.0 to get PC B's subnet which will be different from PC A's like how it will in Case 1, which should again prevent the packet from reaching PC A. ...


3

Hosts on a LAN will never have different netmasks. If I see it as /24 and you see it as /25, we have different networks. Such overlapping networks present numerous problems, not the least of which is the hosts in the smaller block will not know hosts in the larger block are actually "on the wire" with them; they'll send traffic to their gateway (if ...


3

Network classes are long dead, obsoleted in 1993 by CIDR, before the Internet went commercial. You should dump any book on IP from before that year. Classful networking may be interesting for historical reasons but it's completely irrelevant in practical use today. For a private network, just use any subnet(s) from the RFC 1918 ranges 192.168.0.0/16, 172.16....


3

Each IP address must be unique, no matter what its local subnet mask is or what prefix size is used on a route. Let us say, one address in our subnet is 10.0.0.1 (subnet mask /8) If you use 10.0.0.0/8 on any interface you can use addresses from that subnet only on that segment and nowhere else in your network. Now, we decide to create a subnet further, ...


2

In router Please configure default route pointing towards gateway of ISP Router(config)#iP route 0.0.0.0 0.0.0.0 pointing towards ISP gateway


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Router is layer3 divices . With inter-Vlan routing for single interface more VLANs can be configured . For example below Router(config)# int F0/0 Router(config)# no ip address Router(config)# no shutdown Router(config)# int f0/0.10 Router(config)# ip address 192.168.1.0 255.255.255.0 Router(config)# no shutdown Even with single Router interface which is ...


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To accomplish this requirement create a Vlans for each segment and isolate traffic . And further create a access-list that web server is accessible from each Vlan segment independently .


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The purpose of the Subnet Mask is to determine whether the host you are trying to speak to is on your network or on a foreign network. If the other host is on your network, the sending host is going to send the data directly to the other host. If the other host is on a foreign network, the sending host is going to send the data to its default gateway. In ...


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With rare exceptions, Yes. Routers route between networks, so every interface is connected to a separate network. So each interface has an address on the individual network (subnet).


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They're asking you to create 3 different subnets. You're overlapping because rather than carrying on from the 2nd subnet your first operation produced, you're just slicing the same initial net in smaller chunks, so of course they overlap, it's still the same network. Your first operation produced 4 networks, 2nd one being 192.168.1.64, Ideally, you'd want to ...


2

ARP determines the corresponding MAC address for an IPv4 address in the local network (on-link). There's no gateway involved. Since ARP information is cached, there isn't actually that much ARP traffic. IP is designed on the premise that local node-to-node communication doesn't need any central service - it "just works". Also, sending to the ...


2

From a RIR perspective, who has what address space is just paperwork. They don't police who is using what. When a bad actor announces someone else's address space, the proper holder can wave that paperwork in a vain attempt to get them to stop. This hijacking happens often, usually to otherwise unused/abandoned space no one will notice, and more importantly, ...


2

Network and subnet are the same thing in the post-network address class world, and IPv6 never had network address classes, but still uses masks (always written as the mask length, not an explicit mask). An address mask is used to distinguish the network and host portions of an address. It is used to determine the part of the destination address that should ...


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