Re: [Openvpn-users] CPU 100% when waiting for ping-restart

[Markku Leinio <markku.leinio@xxxxxxxxxxxxxx>]

On 4.6.2005 0:00, James Yonan wrote:
> This can occur if you get a routing loop -- in such a case the CPU goes to 
> 100% because OpenVPN is receiving a flood of packets to push through the 
> tunnel, and so is spending a lot of cycles to encrypt/decrypt them.

Oh, there really is a routing issue:

>>push "route <vpn-server-ip> 255.255.255.255 net_gateway"
>>push "route <first-network> 255.255.255.0 default 100"

This first-network actually contains the vpn-server-ip, that's why I
have to enter a /32 route before the first-network.

So, when the network goes down, the route to vpn-server-ip disappears
and OpenVPN tries to reach the vpn-server-ip through the tunnel, which
causes OpenVPN to send the packets to itself, I guess. Ethereal dump
showed only UDP packets going from the local tunnel endpoint (private)
address to the server public address.

I don't see any other way to prevent this but specifying n+1 smaller
routes to cover all other addresses from the /24 than the single
vpn-server-ip, so I will just live with this.

Thanks for your comments.

-- 
Markku Leiniö, Turku, Finland