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1

It turns out it is a routing problem on the switch. Multicast routing for the VLAN in 10.1.1.x is not turned on. Once we added 'pim sparse-mode' on our cisco router. Everything is working as expected.


0

I feel like I might be asking for a downvote here because I have much more educational experience on this topic rather than business application experience. And the commenters have much higher rep than I do. Please be kind. This happens because of your topology. I'm going to assume that you're pinging on the 192.168.0.0/16 subnet? Even if you are ...


0

A Cisco router will not let you have interfaces with overlapping IP address ranges (unless you start looking into VRF's). R1(config)#int fa0/0 R1(config-if)#ip address 10.10.1.2 255.255.255.240 R1(config-if)#int fa0/1 R1(config-if)#ip address 10.10.1.3 255.255.255.240 % 10.10.1.0 overlaps with FastEthernet0/0 To be honest, the topology that you propose ...


1

You're getting into some really difficult problems here :) First question you have to ask yourself is what happens to your data when the primary fails. I'll forget about that for now. Second question is what happens to already-connected TCP streams. "Transparent" would imply that they stay connected, which would almost need you to have active-active ...


1

You can specify the source IP address or subnet with the parameter "-s" and then drop all the traffic from eth1 to eth0 sudo iptables -A FORWARD -i eth0 -o eth1 -m state --state RELATED,ESTABLISHED -j ACCEPT sudo iptables -A FORWARD -s 192.168.1.1 -i eth1 -o eth0 -j ACCEPT sudo iptables -A FORWARD -s 192.168.1.0/24 -i eth1 -o eth0 -j ACCEPT sudo iptables -A ...


4

I think the below entry under Persistent Routes is causing the trouble. 0.0.0.0 0.0.0.0 192.168.144.12 Default Delete it using route delete 0.0.0.0 192.168.144.12 and try.


-3

You should try using google DNS (8.8.8.8 or 8.8.4.4) in the preferred DNS server field. Router address (192.168.144.1) would act as a gateway on this server.


4

This type of configuration is not supported by AWS. VPC Peering does not support "multiple hop" routing. The following configurations are not supported through VPC Peering. VPC A -> VPC B -> Internet VPC A -> VPC B -> VPC C Reference: Invalid VPC Peering Connection Configurations


0

"I didn't test it enough" -everyone I had it in my answer, I am being rejected by Gmail, why though? I'll tell you. It is because I have no MX record at all. I am not coming from a DNS server, but I can fix this by contacting Linode (the hosting service for this project). I will not bother as I do not need to send to anyone but my own exchange for the ...


1

Is there a way to do a 1-to-1 NAT in IPv6 (I'm using Linux machine as a router)? This is known as "network prefix translation" and yes linux does support it. You use the "SNPT" and "DNPT" targets in the "mangle" table (the "nat" table is only used for stateful NAT). How do I do it? You use the SNPT target to change the source prefix on outgoing ...


1

Add to the server config: push route 10.8.0.x 255.255.255.255


6

As stated, this is the way IP was designed to work, and it does work well. NAT introduces annoying problems at times. Some have described NAT's "hiding" of the internal IP as an advantage, but it can also be a disadvantage. I worked in a place with a /16 and we used publicly routable IPv4 addresses on every device (including printers and mobile phones and ...


3

The IPv6 proponets saw NAT as a temporary hack to alleviate IPv4 address exhaustion and hence NAT would not be needed with IPv6. However NAT has a few advantages other than stopping address exhaustion. NAT decouples your internal addressing from your internet connectivity. At least on linux, NAT tends to fail-closed. If the iptables rules fail to load ...


26

Is that how IPv6 is intended to work? In short, yes. One of the primary reasons for increasing the address space so drastically with IPv6 is to get rid of band-aid technologies like NAT and make network routing simpler. But don't confuse the concept of a public address and a publicly accessible host. There will still be "internal" servers that are not ...


14

If there is no need for outside connectivity, then private networks can be used. That is the reason for defining private address space also in IPv6. NAT is a hack that was invented to delay IPv4 address space exhaustion. NAT causes issues with applications, and to get the applications to work with NAT, more hacks are needed which conflict with the original ...


18

We use public IPv6 addresses in our company network for all devices. We use a stateful firewall on our gateway, that: allows all icmpv6 allows new connections from internal network out allows established connections from public to internal No public traffic (except ICMP and established connections) should get into our network. So far we had no problems ...


0

Right now in Azure there is no way to route traffic the way you described. You can either create a site to site link to each vnet (or a point to site connection for testing) You can invest in an Express route connection and use MPLS to swap routing information You could consider using one Vnet with multiple subnets instead of two Vnets, unless you have ...


1

how do I actually validate this Run tcpdump/wireshark, target a specific interface with -i interface and generate some traffic that should go through a specific interface using whatever your favorite tools are. Netcat to a tcp service might be a good option. Make sure you see everything for the connection, with tcp, make sure you see both directions of ...


3

Try using a 6in4 tunnel broker to get IPv6 connectivity. It is more reliable and will work in this case. The brokers I am aware of offer free tunnels. The upgrade is quick and relatively painless. I've been using 6in4 over with IPv6 on eth0 for years.


0

Full Multicast routing gets much trickier (so much easier in the days of hubs). There is a package to install to make it much easier. WiFi is configured to not allow a WiFi device to talk to another WiFi device.


0

So this is the definitive answer i was looking for. You first need to set NAT (prerouting) rule to redirect the traffic to the correct server/computer. Done like this... iptables -t nat -A PREROUTING -p tcp -s yy.yy.yy.0/24 --dport 3389 -j DNAT --to-destination 192.168.1.xx:3389 Then you need a Filter (FORWARD) Rule to allow the traffic to flow to the ...


0

So I ended up using an Etherchannel (ports 23/24 on each switch). I setup VTP. I setup HSRP for fail over routing. This was the key, as with trunks (dot1q). I have my servers running SFT between switches. This way, if one switch fails, I have routing, trunking, and core layer 2/3 capabilities. While it's not VSS, it's getting much of what I need done. One ...



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