Posts Tagged ‘server’

May
11
2010

FIX: VPN server on 2008, no data goes through

This post isn’t a regular “fix” in the sense that I point out a problem that is often overlooked or badly documented. It’s just that after spending so many hours chasing this problem, I felt compelled to share it in case it can help, even though it makes little sense.

The setup: I want to add VPN access to my corporate network, consisting of a few servers behind a Linksys/Tomato router. Most servers are Windows 2008 virtualized on VmWare ESX4i servers (but that doesn’t really make any difference.) The VPN server will be placed on a windows 2008 machine that currently serves WSUS (updates) and anti-virus deployment. DNS, DHCP, domain controller, that’s all on other machines.

I followed the guides I could find on the net, but every time I would be able to log my user on to the VPN, but not access anything (not ping any host).

Finally, I resolved this by uninstalling the role from the Server Admin page, rebooting that box, re-installing the role and re-installing the feature.

It worked right away!

Tags: , , ,
Posted in Fix | 1 Comment »

Mar
24
2010

VMware ESX4i packet loss with VMs

I’ve just finished building this ESX4i server with a few VMs in it and as I plug it into the serve space and into the network switch, I notice that the vSphere console is laggy, to the point of being really annoying.

I ping the server from a workstation, a few packets get lost in transit. I grew the ping packets to 60 kilobytes, and sure enough, about 10% packet loss. I tried pinging the hypervisor management interface, still from my workstation, and I get a slightly lower, but still significant amount of packet loss.

After checking all my cables and trying another network switch, I finally saw that the switch was not illuminating the “Full duplex” light, indicating it was, instead, half-duplex.

Going back into vSphere client, clicking my host in the left menu, then going in the configuration tab, then Networking, then Properties. Second tab “Network Adapters”, then Edit. In there, the Status of my physical NIC was set at 100 mbit Full Duplex (so it should have worked.) I changed it to Auto Negociate and now everything works perfectly. 1800 ping packets transmitted, 0 loss.

Tags: , , , , , , ,
Posted in Fix | No Comments »