Category Archives: Networking

OpenVPN: Listen on TCP and UDP with TUN

Today I’ll describe how to get OpenVPN to listen both to UDP and TCP port, using both¬†tun device¬†and the same network for clients. Meaning the same client can connect on either TCP or UDP and get the same IP Address … Continue reading

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BGP4: Enabling IPv6 Neighbors

Being tired of using static routes with IPv6, I’ve some times ago implemented OSPFv3 with IPv6 peers… But I have faced a lot of issue, mostly due to quagga’s implementation of OSPF.

I’ve decided some days ago to switch to BGP4 IPv6 peers. I have to say one things to summary: It works very well.

You can read the full article to see how I have put this in place.

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Packet load balancing over two ISP

Today I’ve been wondering how to loadbalance my home traffic accross two connexions. I had already done some load balancing but the solutions were only possible using a route-based algorithm so, no real gain from using such a method with … Continue reading

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Cisco: HSRP to improve redundancy

In a previous post, I have talk about how to put in place a heartbeat failover cluster for services. Now I’d like to improve my network redundancy by putting two routers in failover, I’ve achieved this simply by using HSRP … Continue reading

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Dynamips: compute your idle-pc value

Previously, I talked about dynamips and how to run Cisco hardware virtually. I also talked about an “idle-pc” value that you needed to compute in order to reduce the CPU usage of dynamips. Let’s try to compute this value: Start … Continue reading

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Dynamips: cheap cisco hardware

Some days ago, I was facing a migration problem… I had to find a temporary solution to host a Cisco VPN on a fast line where I can’t place a physical Cisco device…

I searched google to see if there were some opensource solution for such VPN server.. But apparently, there is not..

Then I found Dynamips, an IOS software emulator. After reading some docs about it and talking with friends, I decided to give it a try.

You will find hereunder the results of my testings..

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SSH on Cisco

Configure SSH on a Cisco AP with IOS: (config)# crypto key generate rsa (config)# ip ssh time-out 60 (config)# ip ssh authentication-retries 2 To prevent non-SSH login add the following line to all “lines”: (config)# line vty 0 4 (config)# … Continue reading

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