In my views, "Failing to Plan means Planning to Fail". Most project managers and technical leads undervalue the importance of deployment in the solution development life cycle. Deployment planning is often considered even out of solution development perspective, and the complexity of this process is only realized when the deployment sits on the hot seat. In any professional IT products and services providing organization, you would find regular environments like Development, Staging (UAT), APT (Application Performance Testing) and Production. Each of these environments can have different corporate policies that implies a set of security and access methodologies in these environments. So if you have not planned your deployment strategy, each environment can compel you to make changes to your development.
A typical MS BI solution would consist of technologies like Microsoft .NET, SQL Server - SSIS, SSAS, SSRS, MOSS with/without enterprise services, Microsoft System Center, Team Foundation Server, Microsoft Office among the major application and database components. Below are some of the points to keep in view, which can have a huge impact on the overall solution development, and ignoring these points generally would emerge as a show-stopper to develop a generic build and deployment package.
1) Server and Instance names: Generally to make speedy progress development in development systems, often developers use hard-coded database names / instance names / server names. Different environments can have different server and instance names.
2) Service Accounts: Initially when development machines are setup for the team, developers tend to use whatever account has the best privileges or their own account. This would immediately fail in environments where a separate team would be deploying your build and there would be a separate dedicated service account created for an application as per the corporate policies. Also in many secure production environments, network admins keep on changing service account password at regular intervals. So if you are using user id as well as password to access web services and you have not programmed your services to pick up credentials from a configuration store, you just hit another show stopper.
3) Software Configuration: MOSS and .NET development can require creating many proxies and web / service references, which are mostly sourced or build in the form of DLLs. These can make your solution dependent on certain libraries, which are hard to detect as the development would federated across various development machines. This creates a discrepancy in software configuration. Again certain developers might be using different IDEs with add-ons that would dump external DLLs, for example AJAX Toolkit with VS 2008 and Sharepoint Designer. This needs to be carefully planned, as your server environment might not contain all these libraries.
4) Security Configuration: This is one of the most complex bit. Different technologies talking to each other would be communicating mostly through Windows Integrated Authentication or Active Directory Federation Services ( Windows Identity Foundation / Single Sign-On) configured with a claims / token based mechanism. It is quite possible that development environments can have different security configuration than other environments. During development this goes easily out of focus and the prize to pay for this is very heavy afterwards.
Site Collections / Web applications created on MOSS would be using HTTP / HTTPS with certificates which would need to be installed and configured on the site. Corporate policy might not allow you to copy certificates across servers, and this may come to light only when you might want to deploy your solution and infrastructure teams would raise a red flag for certificates.
I have been personally evident of a scenario where different developers developed their SSIS packages with ProtectionLevel property of the package set to EncryptSensitiveWithUserKey. Developers keep joining and leaving the team and they log on to systems using their Active Directory IDs. When the solution was deployed on a different environment, the solution started failing. Now these packages can be fixed only using the credentials of the users who developed them, and this iceberg almost sank the ship.
5) Automation: Many things are done manually like executing DB Scripts, deploying SSRS reports using BIDS, deploying MOSS site using Sharepoint Designer. You would find yourself with a new development cycle, when infrastructure teams responsible for staging and production environments would refrain you from access to these environments.
6) Shared environments: Solutions that are equipped with exclusive servers are quite lucky and also are generally first of their breed or mission critical. In any organization that is having an infrastructure setup in data centres for their IT Services would have shared environment for different application services like SSRS Reporting Servers, MOSS Application Servers etc. One may overlook this detail considering that fact that the same version of the service is used. But at certain levels overlooking key piece of information can be very heavy, for example, one may change web.config file which is the configuration file for entire server. Shared servers would be catering an array of applications, so when you deploy your solution you would not have the luxury of changing these files. At this point again your solution would fail.
Planning your infrastructure followed by deployment can provide insight into many restrictions and dependencies that you may discover very late. And such discoveries can either break your solution or invite a huge effort to develop your deployment setup. Remember one thing, "Failing to Plan means Planning to Fail" !!
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