I believe I have found what was casuing the problem in my case. I have a Realtek R8168 onboard ethernet, but Ubuntu was loading the Realtek R8169 driver.
lspci | grep -i eth output:
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
I followed the instructions here to download and install the proprietary Realtek 8168 drivers:
http://amk1.wordpress.com/2009/06/09/realtek-8168-module-issue/
It's still too soon to know for sure, but so far my VPN connection has been up for over 2 hours (longest it has ever been up without dropping).
I believe I have found what was casuing the problem in my case. I have a Realtek R8168 onboard ethernet, but Ubuntu was loading the Realtek R8169 driver.
lspci | grep -i eth output:
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
I followed the instructions here to download and install the proprietary Realtek 8168 drivers:
http:// amk1.wordpress. com/2009/ 06/09/realtek- 8168-module- issue/
It's still too soon to know for sure, but so far my VPN connection has been up for over 2 hours (longest it has ever been up without dropping).