OSPF has slightly different way of removing routes compared to BGP. On this short post, I will present how a link failure is propagated to other routers on OSPF domain. For this test, I have the following topology section in which AREA3 is connected to AREA0 and we simulate a link failure on the Junos
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What happens when you change a BGP import routing policy in your neighbor configuration? Changes take effect immediately or we need to issue the soft-inbound command to request the routes? Let’s see by an example. We received the route 10.83.0.0/24 from 10.82.1.9 already as you see below. root@J29> show route protocol bgp terse 10.83.0.0/24 inet.0:
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On this micro post, I would like to show one reason why a BGP open message receives a TCP RST. For this test, I set up a BGP neighborship between two peers: PeerA(10.82.1.9) and PeerB(10.82.1.10) PeerA initiates the connection and look what happens in the packet capture. According to the sequence, TCP seems to have
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On this post, I will show an example of loop prevention on OSPF protocol. There is a nice document at here about the principles of loop prevention. What I will just do is to show this on Junos. In order to show this, I am using the following topology; On this topology, J40 and J32
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On this post, I will try to show how OSPF behaves when there are two equal cost paths towards a destination. To demonstrate this, I have prepared my usual topology. On this topology all routers are running OSPF but our focus is on the router J32 which is circled at the bottom and our destination
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OSPF sometimes can be a confusing protocol. For example if you turn on a light switch, you simply get the immediate result: Light is on. What if when you turn on the light switch but you see the shining light bulb after 40 seconds then it is more difficult to understand the result of your
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I was doing couple of tests on BGP protocol today between two EBGP peers and monitoring the BGP trace file I enabled on my Junos box during which I have seen the following NOTIFICATION being sent by one of the peers. GW2 rpd[1144]: bgp_pp_recv:3217: NOTIFICATION sent to 212.6.1.1+59825 (proto): code 6 (Cease) subcode 7 (Connection
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Since the gated daemon, IGP/EGP software has evolved tremendously. I had used zebra long time ago but now to better manage my lab network I wanted to use quagga BGP and OSPF daemons. Quagga is spectacular and its syntax is almost the same like Cisco IOS. After having used JunOS for 2 years, it is
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There may be several reasons why a BGP route isn’t advertised to its eBGP neighbor in JUNOS. I was doing some tests and noticed that one of my routes 172.16.10.0 isn’t advertised to its neighbor. Show route indicates that route is also learned via OSPF as well due to my crap topology at the moment:)
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