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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