The GO service relies on Novell Access Manager to make it work. As the popularity of the GO services increases it places more and more load on the servers that keep GO going. We have been slowly adding in servers to the Access Manager configuration to improve the reliability of the GO service, we are also currently trialing some load balancing software that will make GO more resilient. Last Friday we added another Access Gateway, these Access Gateways serve up the webpages to users (all of the GO pages). If one of the three Access Gateway servers stops running, the load balancer will automatically redirect the users to one of the other servers that are still running.
This week we will be adding in another Identity Server, these servers check usernames and password when users log in, they also mange user permissions and group memberships. This will bring the number of Identity Servers up to two. The last change this week will be to add in another LDAP server, the LDAP servers hold all the usernames and passwords. The two LDAP servers currently in place sometimes struggle with all the authentication requests for GO, WebCT, Blackboard and the Library system. Adding in another server will speed up login times to GO etc. Once the work is complete we will have a far more resilient GO service. There will be 3 Access Gateways serving up the pages and the contect to users, 2 Identity Servers checking user details and 3 LDAP servers storing the usernames and passwords. This brings the total servers that will keep GO going up to 8 servers. Towards the end of this week we may turn the ‘single sign on’ services back on, it depends how smoothly the work planned for this week goes.
In the new year the Core Service team will be working with the Web Services Team to make the servers that provide the content to GO more resilient.