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7

Routing and network protocols are standardized. The Internet is vast heterogeneous network using routers, switches, servers, clients, etc. from many different vendors. Why would you think otherwise?


4

If the providers can filter their updates for you, then that's fewer prefixes to be sent over your links, and fewer for you to process. A common technique is for providers to send you their AS and directly connected customer AS's, in addition to a default route. For AS's that are farther away, it may not matter which provider you use to get there. ...


3

It looks like does not have such command. "show ip bgp", "show ip bgp neighbors 10.0.0.2 advertised-routes" able to find ">" for bestpath. or follow command is work. vtysh -c 'show ip bgp' | grep -i '>' You must run on you OS shell. its better than 'show ip bgp regex'


3

You can use a common non-Quagga-specific recipe: Fire a continuous ping test over the main path established by OSPF. Disrupt the main path. Wait until OSPF restores connectivity for ping. Record how much time elapsed between steps 2 and 3.


3

I think you are looking for the --retain argument, which allows you to retain routes in the kernel across restarts of the daemons.


3

You actually have more than one broadcast link. A DR is per broadcast (or non-broadcast) link, not per area. You can have areas with no DRs, but broadcast links will have a DR (assuming multicast, not unicast, neighbors). In your example, R3 is the DR for the R3-to-R1 link, and R2 is the DR for the R1-to-R2 link.


2

I was asked to provide an answer to this question, to close it out. I may be a little fuzzy on the details as we are approaching 3 years ago now. Essentially we worked around this issue. We wound up adding the required code changes to bird (thanks for the suggestion @drookie), and switching over to use it. We like the fact that it's a more *nix style ...


2

To answer your question directly, this is expected behavior by OSPF and not a bug in Quagga. So first, let's take a look at the DR/BDR section of the RFC. Designated Router The Designated Router selected for the attached network. The Designated Router is selected on all broadcast and NBMA networks by the Hello Protocol. Two pieces of ...


2

Add following line to your rc.conf to instruct quagga's bgpd to retain routes upon termination: bgpd_flags="-r" Quagga's startup script (/usr/local/etc/rc.d/quagga) documented a list of variables and settings you can configure upon startup.


2

If you are specifically looking to speed convergence or lower CPU usage, then asking your providers if they offer a customers+peers+default route option would be the simple solution. If your full-table convergence time/CPU load is acceptable, configuring an as-path-list to limit the number of prefixes you use by AS-Path count provides you more flexibility ...


2

Multicast routing is different than your unicast routing protocols like BGP. PIM is the standard for multicast routing. Every router in the path must support a common multicast routing scheme (sparse, dense, or sparse/dense mode, and any RPs which are necessary), and that usually doesn't happen across ASes because you usually don't have control over neighbor ...


2

They should not differ much (and/or at all) and be inter-operable as OSPF v2 is a ratified standard: https://tools.ietf.org/html/rfc2328


2

I am having the same issue using Quagga (version 1.2.2). I had the --retain flag on the daemon, removed it from my start up script and restarted quagga, but it didn't fix the issue. Only manually deleting the route from the kernel fixed the routing loop. bgprouter# sh ip route 125.209.208.1 Routing entry for 125.209.208.0/22 Known via "bgp", distance 20,...


2

Like access lists, route-maps have an implicit "deny all" at the end. Stanza 90 denies packets it matches, and then everything else is denied by the implicit deny. You need a "permit all" statement at the end like this: ip as-path access-list 20 permit 30$ route-map D1 deny 90 match as-path 20 route-map D1 permit 100 exit


2

This is a quick recipe using Quagga pimd: 1) Setup Host1 static default route towards RouterA (you could also use an static specific route for the multicast group). 2) Make sure Host1 source is sending multicast stream with proper TTL (high enough to reach the receivers). 3) Make sure unicast routing towards multicast source is correct on RouterA. 4) Run ...


2

You can run anything in a network namespace with "ip netns exec". So it should just be a matter of writing some scripts to launch your routing daemon in different network namespaces and with different configuration/data files.


2

Simply assigning a new IPv6 address to an interface does not remove the old IPv6 address. IPv6 allows you to assign multiple addresses to one interface, including addresses from different networks. For example, you will have a link-local IPv6 address. You can then assign multiple global and/or ULA addresses to the interface. In theory, there is no limit to ...


1

In the top image, it appears that the traceroute is actually making it all the way from one host to the other host. I think you are concerned that the intermediate hops are not represented. Traceroute works by sending IP packets with a TTL starting at 1, and increasing the TTL. As a router receives and processes a packet, it decreases the TTL. If the TTL ...


1

There's really no need to change the IP address of the device, as long as your devices support VRRP (since it is linux based, it does) Give to both devices an address within 172.16.1.0/24 (like .2 and .3) and set 172.16.1.1 as a virtual address with VRRP Then configure OSPF on all devices, setting the cost so the primary router will be preferred over the ...


1

So there's a decision tree that just about any router goes through when determining routes. The respective routing protocols (RIP, BGP, OSPF, IS-IS, static) run their own algorithms to determine the ideal path to a given prefix. If the router is presented the same route (i.e. identical network and prefix length) then the administrative distance is ...


1

How do you define cost in Quagga for BGP and RIP? Simply put, you don't. You are comparing apples to oranges. OSPF, a link-state routing protocol, uses cost, but neither RIP nor BGP use cost. RIP is a distance-vector protocol that uses the hop count as its metric, and BGP uses a variety of properties to determine the direction to send traffic. I would ...


1

There are a couple of things going on here: 1.) The maximum metric/hop count in RIP (v1 and v2) is 15. Trying to set a metric of 100 isn't going to get you very far in general. 2.) The "distance" command is administrative distance. This controls the relative priority of routes received in different routing protocols and has literally nothing to do with ...


1

OSPF could work here. I'm not familiar with Quagga, but in a standard setup you could put every interface in the same area and use import policies on Sys1 and Sys2 to prevent them from learning each-ther's downstreams (note you can't set export policies with OSPF), OR put each Sys in a separate area: all areas would be present on the Main router, but only ...


1

How exactly can I routing specific multicast address from Eth1 to OpenVPN_interface_point_B ? This is a configuration sketch to get you started. Host A will send multicast source network 192.168.0.0/24 to Host B by using BGP. ! 1.1.1.1 = Host A ! 1.1.1.2 = Host B ! Host A - partial quagga config for bgpd router bgp 100 neighbor 1.1.1.2 remote-as 200 ...


1

The solution is to have one route-map directly on the BGP network route. This is not documented in Quagga docs (July 2016) but works. network 10.100.0.1/32 route-map localpref150 Complete configuration becomes router bgp 65002 bgp router-id 10.0.0.1 bgp confederation identifier 42xxx bgp confederation peers 65001 65002 network 10.100.0.1/...


1

What you have described is not the way anycast works. For anycast, you have all the DNS servers configured with the same address (usually on the loopback interface), they then participate in the routing protocols and advertise that address from each DNS server. Then the router hears the advertisement from each running server (and, of course, not from any ...


1

No, you cannot change the flag. Attribute MP_REACH_NLRI is defined to be Optional Non-Transitive in RFC4760. What kind of routes you are trying to advertise? Update Neighbor to 192.168.20.201 in same AS(64496) is iBGP, not eBGP. You should be able to fix it easily by changing local AS or neighbor AS. The reason why it wasn't working before you set nexthop ...


1

Yes they can. As Everton mentioned they can already do so even before/during the installation. Quagga is a software on top of a linux/unix kernel. Much the same as, let's say, Firefox on top of Windows. You can install Firefox on Windows on one machine and install Chrome on Linux on another machine. Regardless, the two machines are able to talk to each ...


1

The best guide I found on the topic is Zebra Hacking HOWTO. Other sources of information can be found here. You need to understand how 'threads' and timers work there. I personally prefer look at source code of quagga. It seems not so readable for the first couple hours, but later they're getting OK.


1

The network statements in your BGP router configuration: network 1.1.1.0 network 1.1.2.0 do not match the actual network addresses, which range from /26 to /32. BGP will not advertise networks which do not exactly match what is in the routing table unless you you use the aggregate-address command. Network statements in BGP will not make up routes that don'...


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