Quagga BGP and exabgp: work together for BGP blackhole implementation

Posted 2020-12-17 dream397

 

Quagga BGP and exabgp: work together for BGP blackhole implementation

In our test case we will deploy two machines: 10.0.3.114 for exabgp (it announce /32 prefix for blackholing on core router side) and 10.0.3.115 (it emulates core router). We will do this work on Debian 8 Jessie.

Install exabgp:

pip install exabgp

Create ExaBGP configuration:

vim /etc/exabgp_blackhole.conf

Here you can find example for exabgp configuration:

group Core_v4 {

hold-time 180;

local-as 65001;

peer-as 1234;

router-id 10.0.3.114;

graceful-restart 1200;

 

static {

route 10.10.10.1/32 next-hop 10.0.3.114 community 65001:666;

}

 

neighbor 10.0.3.115 {

local-address 10.0.3.114;

description "Quagga";

}

}

We specify current machine IP as next hop because without it Quagga ignores it: 10.0.3.114 rcvd UPDATE about 10.10.10.1/32 — DENIED due to: martian next-hop;

Start exabgp:

env exabgp.daemon.user=root exabgp.daemon.daemonize=true exabgp.daemon.pid=/var/run/exabgp.pid exabgp.log.destination=/var/log/exabgp.log exabgp /etc/exabgp_blackhole.conf

I recommend you to open log file and look at it:

tail -f /var/log/exabgp.log exabgp

Now we will install Quagga.

Install package:

apt-get install -y quagga

Enable BGP daemon in Quagga:

vim /etc/quagga/daemons

And change following lines:

zebra=yes

bgpd=yes

Then you should create config files and fix permissions for they:

touch /etc/quagga/zebra.conf

touch /etc/quagga/bgpd.conf

touch /etc/quagga/quagga.conf

chown quagga:quagga /etc/quagga/bgpd.conf

chown quagga:quagga /etc/quagga/zebra.conf

chown quagga:quagga /etc/quagga/quagga.conf

Create BGP configuration:

vi /etc/quagga/bgpd.conf

Example for configuration (please be aware! It’s not suitable for production):

hostname SoftBGP

password zebra987

enable password zebra987

log file /var/log/quagga/bgpd.log

 

debug bgp events

debug bgp filters

debug bgp fsm

debug bgp keepalives

debug bgp updates

 

router bgp 1234

bgp router-id 10.0.3.115

bgp log-neighbor-changes

 

neighbor 10.0.3.114 remote-as 65001

Apply configuration:

/etc/init.d/quagga restart

Wow! We see this announce in Quagga:

/usr/bin/vtysh -d bgpd -c "show ip bgp summary"

BGP router identifier 10.0.3.115, local AS number 1234

RIB entries 1, using 112 bytes of memory

Peers 1, using 4568 bytes of memory

 

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd

10.0.3.114 4 65001 12 18 0 0 0 00:01:12 1

 

Total number of neighbors 1

Check announced subnets from exabgp:

/usr/bin/vtysh -d bgpd -c "show ip bgp"

BGP table version is 0, local router ID is 10.0.3.115

Status codes: s suppressed, d damped, h history, * valid, > best, = multipath,

i internal, r RIB-failure, S Stale, R Removed

Origin codes: i - IGP, e - EGP, ? - incomplete

 

Network Next Hop Metric LocPrf Weight Path

*> 10.10.10.1/32 10.0.3.114 0 65001 i

 

Total number of prefixes 1