BGP Outbound Route Filtering
Nov22

BGP Outbound Route Filtering

BGP Outbound Route Filtering (ORF) is a way for a BGP peer to signal another peer what prefixes it wants to receive. This is commonly used by service providers to allow customers to influence what prefixes are advertised by the provider without the provider needing to maintain outbound policies for each customer. The feature is only valid between eBGP peers using a prefix list. In this case we have router service_provider peering with...

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Perl script to update INE CCIE initial configs
Sep30

Perl script to update INE CCIE initial configs

I’ve been using INE’s Workbook-1 to study for the routing & switching CCIE. I recently updated my v4 home lab to virtual 1000v routers running on a UCS server(stay tuned for the post). I love the flexibility of the virtual environment and the ability to create new topologies with only the addition of a new sub-interface. This week I started on the BGP labs and quickly found that there are about 15 different initial...

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EIGRP summarization and route to Null0
Jul30

EIGRP summarization and route to Null0

Automatic creation of a route to Null0 when creating a summarization route in EIGRP is usually a good thing but there will be times where it will cause a loss of connectivity. Keeping this behavior in mind and knowing a few options of how to deal with it will save you some time. In this case R3 is acting as a gateway of last resort by only injecting a default route into EIGRP AS 100 and there is full connectivity between R1, R2 and...

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Perl Script Based on SNMP Uptime
Jul30

Perl Script Based on SNMP Uptime

I had a task to SSH to any router with an uptime of 36 weeks or less and gather some information. Here is some perl code when run on a Linux server will allow you to determine the uptime via SNMP and then take action if the uptime is less than 252 days. open(fileIN,’hosts.txt’) or dienice(“Cannot open hosts.txt: $!”); @hosts = ; close(fileIN); $string “”; foreach $host (@hosts) { chomp($host);...

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INE Workbook-1 basic L2
Jul30

INE Workbook-1 basic L2

I spent a few hours working on the begining of INE Workbook 1 exercises. I got to 1.10 before calling it quits for the day. I worked out a few kinks in the lab like the console connection not working for BB2 and BB3 as well as I was missing CAT5 cables between SW2 and SW3 which was causing some odd results. One of the biggest things I noticed was the need to be able to reference and correlate your network diagram with your physical...

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*Longmode; required when virtual machine is configured for a 64-bit OS / UCS-C200-M2
Jul30

*Longmode; required when virtual machine is configured for a 64-bit OS / UCS-C200-M2

I encountered an error today when trying to create a 64 bit Windows 2008 VM in ESX 4.1-U1 even though this was not an issue on an identical server I received, installed and configured at the same time, exactly the same way. Both ESXi hosts were in the same vCenter data center. It took a fair amount of research to determine what I needed to do on my server so I thought a quick post was in order. The error was: *Longmode; required when...

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