Scope, Objectives and Deliverables
The project’s scope is to decommission the Euclid Web Tier, as the Web servers will not be supported any longer from 31st July 2013, and set EUCLID as a two-tier architecture model.
- To move the Web Tier functionality to the Application Tier.
- To reconfigure the Application Tier.
- Production of migration method. This will include identification of the Web Tier functionalities to be moved to the Application Tier: static files, style sheets, HTS files, java files…Some of the directories already exist on the Application Tier but are set to inactive. Need to update SITS System Parameters.
- Testing strategy: functional and performance (must include success criteria), consider resilience test.
- Updated technical architecture document.
- Implementation process. Consider the options for implementation in order to mitigate the risks: decommission servers gradually, over the two sites. Include back out plan (i.e. re enable access through the web servers).
- Migrated system. All the Euclid environments need to be updated (Dev, Test, Live and Trn). Dev environment is a shared server, which may be used for other purposes, to be checked.
- Client machines are not affected.
- No downtime will be required downtime, as the change could be implemented as follows: take AT offline, make the change then bring it back. Next take KB offline. There would need to be an at risk period though (it requires a urmon restart after the system parameters and files changes).
Out of scope
- Dust environment will not be changed as it is not used.
- No change to the database tier is required.
- There are no security implications.
This project will enable a new 2 tier architecture model for EUCLID fully supported by our suppliers. It is expected that reducing the infrastructure (by removing the six web servers) will bring positive effects: less failure points, less maintenance, and EUCLID should actually be more resilient.
EUCLID is set on two-tier architecture.
All functionalities previously listed on the Web Tier are working, business as usual.
EUCLID performance is the same as before.
Current performance/load test criteria are met.
Check that the extra load on the App Tier is not negatively affecting the performance of client/server or the batch jobs running on the App Tier: need to have measurements for key tasks from before and after the reconfiguration.
Demonstrate how little work the current web tier does.
No load test is required, as there is currently little activity on the Web Tier.
All EUCLID environments have been migrated.
EUCLID will not lose resilience or robustness, and load balancing will continue.
Current resilience criteria are met.
When taking a machine of the load balance, the remaining 5 machines keep the same degree of resilience.