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15

No. The hops shown by traceroute show the path that an IP packet follows on a routed (layer 3) network. Routers will show up, and switches will not. Switches are by their nature a layer 2 device: they receive and forward Ethernet frames, using the destination MAC address to determine the correct destination port. Some switches are also able to function as ...


10

You can see that info also when you run the route print command. It's the first thing displayed. The index is the first column =========================================================================== Interface List 13... ......Bluetooth Device (Personal Area Network) 10... ......Intel(R) 82566MM Gigabit Network Connection 11... ......Intel(R) ...


9

I made a diagram that may be helpful: With regard to static routing, consider the above diagram. We have three separate networks: 192.168.1.0, 192.168.2.0, and 192.168.3.0. At first, network hosts (routers, computers, etc.) can only communicate with other hosts that are on their own network. For instance, the computer named James has a single interface ...


9

From a network performance standpoint, if the public IP addresses are also on the same LAN as with the private address configuration (where all the systems are on the same subnet configuration(s)), then they are functionally equal in network routing/transport. One slight advantage on the private IP plan side would be layer 3 separation from others "snooping"...


8

The types of the routes with the ! flag are either unreachable or prohibit. route, being an ancient utility from net-tools, does not differentiate between the two. Use iproute2. The net-tools way to delete these routes would be to use route del on it. However, net-tools provides no way to differentiate between the rejected route and the other one (...


7

Use the bonding infrastructure at the 'home' and 'vpn1' side, and specifcally with the mode=3 setting which broadcasts traffic on all interfaces which belong to a bond. For more information on how to configure bonding, see the excellent manual at http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.37.y.git;a=blob;f=Documentation/networking/bonding....


6

I used the answer provided by @user48116 and it works like a charm. The setup is actually quite easy! NOTE: I implemented this with two connections to just one single server, as this already solved the problem for me. If you want to try a setup with two servers, the easiest way is probably to use port forwarding to forward the UDP port from the second ...


6

Is the desktop on 192.168.16.0/24? You cannot add a route (to any target) via a gateway which you are not directly connected to, because your computer does not know how to find it's way to the router without going through the default route.


6

It is indeed a linux kernel bug, probably since version 2.6.39. I have posted the question to lkml and netdev lists (see the thread at https://lkml.org/lkml/2011/11/18/191), and it was just discussed in a different netdev thread at http://www.spinics.net/lists/netdev/msg179687.html The current solution now is either a reboot or to flush all routes and wait ...


6

Strictly speaking, you loose complete control of inbound routing paths when you announce your prefix to multiple providers because there are independent routing decisions made downstream for return traffic to you. Furthermore, your announcements could even be modified by downstream providers after you send them. Example This is one example of what can ...


6

No, it does not. The subnet mask is used exclusively for routing decisions (the routing algorithm needs a hint what hosts are local and what needs to be sent to a gateway), the addresses have to be unique in any case. See also: http://en.wikipedia.org/wiki/IP_forwarding_algorithm But you can set the netmask arbitrarily to match your requirements on subnet ...


6

A layer 2 switch won't show up in a tracert because it's a layer 2 device (a switch) and simply forwards (switches) traffic from one switch port to another based on the layer 2 address of the destination device. Tracert (ICMP) works at layer 3. In order for the switch to show up in tracert it has to be in use as a layer 3 device (a router) and has to be in ...


6

I'm assuming that you want to RDP to it so that you can change it's ip address? If yes, then you can try this: Temporarily assign your workstation an ip address in the same 172.18.2.x range, then RDP to the machine, then change the ip address to match your new ip address range, then change your workstation ip address back to what it was.


5

ip route works like ip route <these destination IPS> (via) <this ip> (Don't actually include the word "via"). So the final IP in the command is the next hop those packets should take. This could also be an interface on the router itself instead of an IP of a neighboring router which is commonly used when you have point to point connections. ...


5

The 149.x.x.x host wouldn't be on your local subnet, so your computer would have no way of contacting it. A router between your subnet and that subnet should have both a 149.x and a 172.x address (on two different NICs hopefully), it would route between the two subnets.


5

About 6 servers connected to an unmanaged Dell switch Assuming both IPs are on the same interface, or they are on different interfaces, that connect to the same unmanaged switch, then there really is no difference. I would be slightly concerned that there is no firewall/edge device between your systems and the network provider.


5

See http://www.linuxfoundation.org/collaborate/workgroups/networking/tunneling#IPIP_tunnels and the paragraph below. Basically it's that IPIP can handle only IPv4 unicast, no multicast traffic and only one tunnel for unique tunnel endpoints pair. GRE is more generic, with up to 64k tunnels between two unique endpoints plus multicast traffic which is ...


5

This is done with Variable Length Subnetting. To do VLSN we just look at all our networks and arrange them in size. First the big ones then the smaller ones. You already have your /24 networks so to correct your subnets: if you have 10.12.0.0 and you need 6 /24 networks and 2 /27, then we need to first accommodate the /24 networks: So we get: Subnet 1: ...


5

Update After discussing this in chat, we determined the problem was handling the static routes between 10.1.1.2. and 10.1.1.1. There aren't any hosts connected to 10.1.1.2, but if there were, there would be no way to route traffic to 10.1.1.0 and get that traffic to both groups of hosts. Even with no hosts, getting to the router itself (for admin purposes) ...


5

I think you're looking in the wrong place. Check your basic network settings in the Network preferences pane in System Preferences before you go looking at the raw routing tables. I'm pretty sure what you'll see is that your en1 port has a self-assigned IP address of 169.254.174.250, and no router address. The UI doesn't always explicitly indicate that it's ...


5

This seems way too complex. Just bridge the VM and set the IP address in the guest.


4

Here's another example, with basic filtering (no RFC1918 inbound routes, only advertise your local prefix: router bgp YOURASN bgp router-id BGP_ROUTER_IP_ADDRESS network 209.85.171.0/24 neighbor myisp peer-group neighbor myisp remote-as ISPASN neighbor myisp distribute-list 3 in neighbor myisp distribute-list 4 out neighbor myisp filter-list 2 out ...


4

with the route -n command you'll obtain Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.178.1 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 160.98.123.1 0.0.0.0 UG 600 0 0 wlan0 sudo route del -net 0.0.0.0 gw 192.168.178.1 netmask 0.0.0.0 ...


4

I think it's this: route del -net 10.1.0.0 netmask 255.255.0.0 metric 2 I'm not 100% certain. But, I think you've got something else goofy going on since you have 2 default routes.


4

I suspect you may be running into an issue with the reverse path filter. Which is designed to perform some checks to make sure that the packets received on a given interface actually belong to that interface. # from linux-doc-nnn/Documentation/networking/ip-sysctl.txt rp_filter - INTEGER 0 - No source validation. 1 - Strict mode as defined ...


4

Routing table information is privileged and can only be seen by unauthenticated users in cases where one of the following is true: The administrator of the next hop device has left it in an insecure state that allows anonymous access. The administrator of the next hop device has created some kind of special and intentional public interface to show the ...


3

I wrote about IPv4 subnetting and routing in an earlier posting. I didn't talk about layer 2 / layer 3 interaction there so, being that I'm stuck in a hospital waiting for a friend's baby to be born, I'll go ahead and expound here a bit. IP, being a layer 3 protocol, gets encapsulated into a layer 2 protocol when IP datagrams are put onto a physical (layer ...


3

BGP is not a load balancing protocol. Let me repeat that, BGP is NOT a load balancing protocol. If ALL traffic goes out a single connection, my first guess is that you aren't getting a full feed from the provider that is being ignored. Routing is such that precedence is given to more specific routes, so if you have a route of 192.168.0.0/23 going to ...


3

This is the probable minimun you require within your bgpd.conf. router bgp YOURASN bgp router-id 74.125.53.103 network 209.85.171.0/24 neighbor 74.125.53.104 remote-as ISPASN It isn't pretty and you really should add some prefix lists etc before you start looking at adding multiple upstreams just so you don't accidently advertise the entire global ...


3

As it said, add a float option to the client config and try again. --float Allow remote peer to change its IP address and/or port number, such as due to DHCP (this is the default if --remote is not used). --float when specified with --remote allows an OpenVPN session to initially connect to a peer at a known address, however if packets ...



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