The availability of a remote access VPN infrastructure is largely centered around the concentration point of RAVPN tunnels. This chapter has focused on presenting designs scenarios that can be used to increase the availability of RAVPN concentration points. The designs presented in this chapter include:
All of the RAVPN design concepts discussed in this chapter can be deployed in tandem to maximize RAVPN accessibility for IPsec VPN clients. However, tying all of these components together can be daunting. Keeping that in mind, it is helpful to approach designing HA and load balancing in to the RAVPN in a layered format presented in this chapter:
In this chapter, we have covered the basic construction of a remote access VPN deployment, and applied the Local and Geographic HA concepts discussed in Chapters 6 and 7 to that construct to yield several highly available RAVPN design alternatives. In addition to RAVPN HA, we have embedded several effective means by which to load balance inbound client IPsec VPN sessions on a concentrator cluster. Lastly, the concept of multiple peers was introduced to provide the clients with Geographic HA by leveraging the use of geographically disperse and redundant IPsec VPN concentrator clusters.