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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It can be annoying if you are new to SRX and your SSH connection towards the firewall keeps timing out. You can of course activate keep alive on your SSH client or play with the default ssh timeout on SRX itself. First let’s see how we can check the current timeout. root@J200> start shell user
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After a year of being away from SRX, I have noticed that I forgot the CLI command to set a static hostname to IP mapping. If you haven’t used this feature so far, it simply allows you to have a /etc/hosts file similar to what we have in Linux and here is how we set
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I think most of us watched the movie Inception in which there was dream within a dream. It was a bit of confusing at some point. There is a Linux version of it 🙂 terminal within terminal provided by the fantastic tool tmux (terminal multiplexer). I use this tool during some troubleshooting scenarios when I
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I have recently changed the domain name of this blog from rtoodtoo.net to rtodto.net. My intention was to buy r2d2.net in the first place but very smart people bought it long time ago before me:) I couldn’t even find the r2d2.nl available. Now I think there isn’t much make sense to have such a long
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Rest in peace Kenny… http://www.bbc.com/news/entertainment-arts-37072736
Here is a quick python script which calculates average, variance and standard deviation. This is also part of codeacademy work. I must say last time I worked with variance and standard deviation it was more than 10 years ago in statistics course. Hence a bit of reminder here for me too: (Some are from wikipedia
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Today I have stumbled across a system resource utilization tool htop which is way more visual than top and it is easier to use too. For example, following is from my single core amazon cloud centos server. You can easily see that sorting is by CPU and if you want to change it, just press
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I have written a simple python game script to sink a battleship. It is very simple as it was almost a year ago last time when I wrote a long python script. Thanks to codeacademy that it helps to brush up my python skills. I think it is also good to put the script here
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