OSPF – Router ID

When a router is running OSPF the OSPF process will select and use a Router ID. This ID must be unique inside of an OSPF area.

This ID will not change unless the process is restarted or otherwise cleared. This is due in part as a topology convergence will be …

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Powershell Converting from Filetime

If you have ever worked with Powershell you send up running into DateTime stamps that are stored in FileTime instead of DateTime.

You can easily convert these to a date time object with the DateTime type accelerator.

PS C:\> [datetime]::FromFileTime(129948127853609000)
Monday, October 15, 2012 3:13:05 PM …
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Spanning Tree : Root Bridge Election Process

STPs root bridge election is something that I have to look up every time I need to look up every time that I need to work with it. So here are some quick tips for working with root Bridge election. This will show examples from Cisco switches but the concepts …

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Final parts – IPsec part 4

  • In part 1 I laid out the general configuration that I will be disusing through this series of posts.
  • In Part 2 I discussed ISAKMP polices.
  • Part 3 I discussed Transform-sets
  • Part 3 I will wrap it up and go over the last parts.

Pre-shared key

As we are using …

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Transform-set – IPsec part 3

  • In part 1 I laid out the general configuration that I will be disusing through this series of posts. Part 1
  • In Part 2 I discussed ISAKMP polices.
  • Part 3 will be a shorter one about Transform-sets

Transform-set

Transform-sets are the ciphers that will be used in the actual Data …

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ISAKMP Policy – IPSEC Part 2

  • In part 1 I laid out the general configuration that I will be disusing through this series of posts.
  • In Part 2 I will be discussing ISAKMP polices.

ISAKMP Policy

crypto isakmp policy 10
     hash md5
     authentication pre-share

Internet Security Association and key management Protocol (that’s a mouth full …

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TarSnap – Online backups for the truly paranoid

I recently set up a backup solution for my Linux servers and I ended up going with Tarsnap for the cloud storage. I did this for a couple of reasons. The backup tool was built in the Unix fashion and does only the bare minimum of backup tasks, but it …

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IPsec part 1

I have started learning about IPsec and related technologies.

But this is a very large subject that I will go going quite in-depth with so I will be doing this as a multi-part post over a couple of weeks.

Setup

To get started I followed a pretty good Cisco guide …

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Cisco’s Built in TDR cable tests

Many Cisco Switches (3750, 2960x) support some basic cable tests that can be run from the CLI.

To start the tests you run

Switch# test cable-diagnostics tdr interface g0/1
TDR test started on interface Gi0/1
A TDR test can take a few seconds to run on an interface …
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Automatic updates with Debian

Though I am taking some risk by automatically updating my servers. I prefer that they always update so that security patches are applied very quickly. Here is how I configured my Debian servers (jessie) to update on a daily bases.

I created a shell script in /root/update.sh

apt-get …
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