Hi,
I worked for Rackspace previously and had access to Vyatta before customer release. Moved on from Rackspace before customer release of the product, but have good picture how they set it up. Also I would advice to have Client VPN running on Cisco device (if it's a firewall) and hairpin access to the Infrastructure behind Vyatta.
I am in full time employment Monday to Friday 8:30 - 17:30 GTM/UK hours, but I could work on setting up the VPN in the evening or over the weekend, fully tested.
Regards,
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