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6

As mentioned by Ron, you can use no-export (Don't advertise to any eBGP peers) or no-advertise (Don't advertise to iBGP or eBGP peers) to achieve this. However, this may strain scalability issues if bringing on another eBGP peer which you do wish to advertise these to. What I'd recommend is applying an inbound route-map/policy-statement on AS200/DUT for the ...


5

Another aspect to and expanding a bit what zac67 already gave in his answer: VLAN IDs used on tagged (sub)interfaces of routed interfaces (a.k.a. no switchport) can be completely independent from the switch's "switching" context [1]. In extenso: the VLAN tag used on the subinterface does not appear as a L2 VLAN on the switch, neither consumes nor ...


5

Yes, absolutely; there are a variety of ways to accomplish this. I'll suggest two just to give you some inspiration. Match Protocol option On your route-map toward the BGP neighbors, you can match protocol connected in a stanza to determine whether you propagate those routes. For example: route-map to-isp deny 100 description don't announce my connected ...


4

Yes. It will be dependent on the exact operating system that runs on the router, but generally redistribution is configured on the router level. I.E. apply to all peers. You can however filters routes that are announced to peers based on various criteria, and especially communities. So one way of doing this is: apply a route-map on the "redistribute ...


2

A subinterface is part of a physical interface, used for a single VLAN. Usually, you only have those for routed interfaces (L3) that do not take part in L2 forwarding = switching. An SVI (switch virtual interface) is a network-layer binding to the VLAN instance itself, used for routing, management, DHCP, ... - any higher-layer function apart from L2 ...


2

According to examples across the web, if two routers are directly connected with an ethernet cable, this is a point-to-point network (which totally conforms to rfc point-to-point definition). but if there is a switch between routers, that makes a broadcast network. how it is concluded from rfc definition. You can define a network by the topological ...


2

Trying to use some kind of retaliation is a bad idea. The source IP address you see may be spoofed, or some kind of amplification attack may be used. It is also quite possible that the attacker notices your attempts and intensifies the attack - very often, they've got significant resources, so beware. Retaliating likely solves no problem and causes new ones. ...


1

There are well-known communities called no-export and no-advertise that you can use to tag prefixes to prevent them from being advertised to a different AS or even different internal routers. Use a route-map to tag the incoming prefixes as you want.


1

When you have a layer-2 configuration with VLANs, each VLAN basically acts as a virtual switch. That's the point of VLANs, after all. You can think of the traffic flow as coming in through a port, getting split up (demultiplexed) into different VLAN flows, getting L2-switched independently in each VLAN, and then on the outgoing side, flows from different ...


1

Since dual is the algorithm that is used by eigrp to prevent routing loops in the eigrp AS it would have to track changes in the network including neighbor adjacencies. If a neighbor adjacency fails or a new adjacency occurs this would be relevant to the adjacency table so I could see it would have to be involved at some level with the adjacency table. ...


1

A broadcast network is what you've got on an Ethernet switch (or multiple connected ones): any node can talk to any other directly. If there are VLANs, each VLAN represents its own broadcast network/domain. The distinction that RFC makes is the contrast between a broadcast network with point-to-multipoint addressing, a non-broadcast network with P2MP, and a ...


1

On a DHCP server (which may be integrated in a router), you can configure multiple scopes with one or more address pools each. Each scope matches a local interface subnet or is used with a relay, which in turn is used for address matching (per option 82, sometimes policies are used). DHCP options like DNS server and routers are usually configured on a scope (...


1

I believe pool is chosen by the incoming interface of the router or DHCP relay. Router match pool which addresses are matching incoming interface network/netmask. Several pools on a router(R1) may not be tied to R1 interfaces because DHCP packet can be received through router/DHCP relay(R2). In that case relayed packet will also have a field of incoming ...


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