Hello,
Any hints will be greatly appreciated !
Cheers
—
Cédric Lemarchand
> On 25 Feb 2017, at 18:03, Cedric Lemarchand <yipik...@gmail.com> wrote:
>
> Hello Ondrej,
>
> Thanks for your precious explanations. Unfortunately I am still stuck, static
> routes does not apply between 2 hosts.
>
> To solve 1) and 2), and in the way I only need to publish static routes to
> other BGP hosts, I changed "export all” by "export where proto = “static1” “,
> but still no luck. I notice that static routes are not received any more on
> hosts.
>
> Here is my understanding of “show protocol all” on host1 :
>
> direct1 Direct master up 17:35:58
> Preference: 240
> Input filter: ACCEPT
> Output filter: REJECT
> Routes: 2 imported, 0 exported, 2 preferred
> Route change stats: received rejected filtered ignored accepted
> Import updates: 2 0 0 0 2
> Import withdraws: 0 0 --- 0 0
> Export updates: 0 0 0 --- 0
> Export withdraws: 0 --- --- --- 0
>
> Bird finds 2 direct routes related to eth0 and eth1, so they are received,
> accepted, but not exported, which is fine.
>
> kernel1 Kernel master up 17:41:12
> Preference: 10
> Input filter: ACCEPT
> Output filter: REJECT
> Routes: 1 imported, 0 exported, 1 preferred
> Route change stats: received rejected filtered ignored accepted
> Import updates: 1 0 0 0 1
> Import withdraws: 0 0 --- 0 0
> Export updates: 6 5 1 --- 0
> Export withdraws: 0 --- --- --- 0
>
> Bird find 1 static route and try to export 6 routes but they all get rejected
> or filtered, which is fine too, but I dont know why “6” routes of the routing
> table bellow :
>
> root@host1:~# ip r
> 10.10.1.0/24 dev eth0 proto kernel scope link src 10.10.1.1
> 10.10.2.0/24 via 10.10.1.254 dev eth0
> 192.168.1.0/24 dev eth1 proto kernel scope link src 192.168.1.1
>
> device1 Device master up 17:41:12
> Preference: 240
> Input filter: ACCEPT
> Output filter: REJECT
> Routes: 0 imported, 0 exported, 0 preferred
> Route change stats: received rejected filtered ignored accepted
> Import updates: 0 0 0 0 0
> Import withdraws: 0 0 --- 0 0
> Export updates: 0 0 0 --- 0
> Export withdraws: 0 --- --- — 0
>
> Nothing to say about this one, from what I have read it’s role is to feed the
> kernel protocol.
>
> static1 Static master up 17:41:12
> Preference: 200
> Input filter: ACCEPT
> Output filter: ACCEPT
> Routes: 1 imported, 0 exported, 0 preferred
> Route change stats: received rejected filtered ignored accepted
> Import updates: 1 0 0 0 1
> Import withdraws: 0 0 --- 0 0
> Export updates: 0 0 0 --- 0
> Export withdraws: 0 --- --- --- 0
>
> This one is annoying me and I think the issue is there, 1 imported but
> ignored, why ?
>
> bgp1 BGP master up 17:41:13 Established
> Preference: 100
> Input filter: ACCEPT
> Output filter: (unnamed)
> Routes: 0 imported, 0 exported, 0 preferred
> Route change stats: received rejected filtered ignored accepted
> Import updates: 0 0 0 0 0
> Import withdraws: 0 0 --- 0 0
> Export updates: 3 0 3 --- 0
> Export withdraws: 0 --- --- --- 0
> BGP state: Established
> Neighbor address: 10.10.2.1
> Neighbor AS: 3000
> Neighbor ID: 10.10.2.1
> Neighbor caps: refresh restart-aware AS4
> Session: internal multihop AS4
> Source address: 10.10.1.1
> Hold timer: 162/240
> Keepalive timer: 53/80
>
> I don’t understand why 3 routes are received because protocols direct1 and
> kernel1 should not export anything, and only one static route should be
> received via BGP from host2 ! Also the ouput filter is unamed, which I thinks
> is not good.
>
> Below the host1 bird.conf.
>
> As you can see I think I misunderstand some things, and I am a bit
> disappointed.
>
> Cheers
>
>
> router id 10.10.1.1;
> protocol direct {
> interface "*"; # Restrict network interfaces it works with
> }
> protocol kernel {
> learn; # Learn all alien routes from the kernel
> #persist; # Don't remove routes on bird shutdown
> scan time 20; # Scan kernel routing table every 20 seconds
> import all; # Default is import all
> export none; # Default is export none
> }
> protocol device {
> scan time 10; # Scan interfaces every 10 seconds
> }
> protocol static static1 {
> route 192.168.1.0/24 via 10.10.1.1;
> export all;
> }
> protocol bgp {
> multihop;
> #gateway recursive;
> import all;
> export where proto = "static1";
> local as 3000;
> neighbor 10.10.2.1 as 3000;
> #next hop self;
> #rr client;
> }
>
> —
> Cédric Lemarchand
>
>> On 23 Feb 2017, at 17:10, Ondrej Zajicek <santi...@crfreenet.org
>> <mailto:santi...@crfreenet.org>> wrote:
>>
>> On Thu, Feb 23, 2017 at 04:42:50PM +0100, Cedric Lemarchand wrote:
>>> Yes, I am not sure to understand how plays theses options (and if I need
>>> it) in the bgp protocol and it they are related to my problem :
>>>
>>
>>
>>> gateway recursive : means that if host2 advertise "route 192.168.2.0/24
>>> via 10.10.2.1;” to host1, host1 does a lookup in the kernel routing table
>>> and set the nexthop for 192.168.2.0/24 via the same IP as for host2 ?
>>
>> Mainly yes, but:
>>
>> 1) Not lookup in the kernel routing table, but in the BIRD table. By
>> default the same table as used by BGP protocol, but could be configured
>> to different one by 'igp table' option.
>>
>> 2) It is not lookup for host2, but lookup for bgp_next_hop attribute, as
>> specified by host2, which is usually value of 'via'.
>>
>>> next hop self : means that every route advertised by host2 will be routed
>>> to it self while keeping the “gateway recursive” logic ?
>>
>> That means host2 always announces own IP address as bgp_next_hop instead
>> of one from 'via'.
>>
>>> The output of show route all :
>>
>> There are two issues:
>>
>> 1) both hosts announce all routes (not only 192.168.xx but also 10.10.xx).
>>
>> 2) routes from kernel1 protocol has lower preference (10), so routes
>> from BGP are preferred and you get circular lookups for 10.0.1.1, 10.10.2.1
>>
>> You could change preference of kernel protocol to say 200 and you
>> could filter out unwanted routes in BGP export filter.
>>
>> --
>> Elen sila lumenn' omentielvo
>>
>> Ondrej 'Santiago' Zajicek (email: santi...@crfreenet.org
>> <mailto:santi...@crfreenet.org>)
>> OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net
>> <http://wwwkeys.pgp.net/>)
>> "To err is human -- to blame it on a computer is even more so."
>
