admin

We use Microsoft PPTP as our VPN solution at work. Although PPTP is not robust as a IPSEC based vpn, it is a lot easier to deploy and maintain. The biggest advantage is that most of the Microsoft OS’s (Windows 2000, XP, 98) have PPTP clients built into the OS. With IPSec, one has to deploy client software to the workstations. Recently SSL VPN‘s have made strides in the remote connectivity market and are even easier to maintain.. but that is for another post.

We had a very interesting problem with remote users trying access hosts/URLs in our network recently. We have several nodes in the network, which we publish on external and internal DNS. So users on the internal network would access the node via the internal IP address and get access to privileged areas, while public users accessing the node would be restricted to only some areas of the site. Users connecting to the office network via VPN were being directed to the external address even though their VPN was configured to use the remote gateway as the default gateway. This in theory should direct all traffic to the internal network. We scratched our heads for a while 🙂 and during the troubleshooting session discovered that the DNS of the node was resolving to the external IP address. So the workstation was using the DNS server provided by the ethernet interface rather than the PPTP interface!!!.. How do we solve this?? Well Google, to the rescue and we find this obscure article on Mircrosoft’s website, which tells you how to change the bind order of the network interfaces so that the PPTP interface is used by default. Since this is a registry change, we have to figure out a way to push this out to the workstations. But that is a story for another post :)..

Cacti is a great tool to graph network utilization. I discovered it during my previous job to create some utilization graphs of satelite links. I highly admire the talent of the kid maintaining this software… Cacti can be used by any organization wanting to graph network utilization. It is also flexible enough to graph other stats (disk utilization, CPU utilization.. etc.)

I used Linux for all of my previous installs of Cacti. The whole install is very well documented. My team is still not very Linux savvy and wanted to try Cacti out in a Windows environment. There is adequate documentation for installing Cacti on Windows, but I ran into several issues when following this guide. If I was starting all over again, I would rather try this documentation. It is more up-to-date and detailed. The author missed mentioning that you have to change the “DocumentRoot” value in the Apache conf file.. But that is a minor issue.

Am still having issues with the scheduler tool in Windows to run the poller every 5 minutes. The scheduled job is only running when someone is logged into the server. As soon as you log off the server, the scheduler seems to be stopping. I will post an update as soon as I fix this.