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Management System of control for the release of versions of web systems based on ITIL using Unix Shell

Autoria: Oscar Dalfovo, Rion Brattig Correia, Camila da Silva Schmitt, Jeferson Samagaia

ABSTRACT A model of Information Technology (IT) services best practices, the Information Technology Infrastructure Library (ITIL) has the objective of supplying services with quality scores, so, this study presents the specification and development a web environment for the management of releases based on ITIL recommendation. The system uses the subjects of change management, release management and configuration management. The aim of these subjects is to ensure that implementations have the least possible impact on environment of production. The use of this shell allows the monitoring of the liberation process by sending an informative to the users involved during the approval flow.

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1 INTRODUCTION

Seeking improvement on the work flow, large companies have sought investing in business processes in order to optimize the complexity of current systems. In order to maintain a stable environment, the companies invest in automation and changes of business processes. The control of versions release is a great business strategy to avoid unavailability and enterprises infra-structure stability losses, in addition to ensure the correct implementation of newly-approved systems. Through this process, all implementations and changes in Information Technology (IT) infra-structure will be analyzed and planned so it has the lowest risk and impact on production environment (GSTI, 2006, p. 49).

The changes implementation frequently happens with the release management activities with the objective of controlling the distribution of hardware and software, including integration, testing and storage using processes and formal checking (ITILFOUNDATION, 2006, p. 35).

The developed system aims to automate the whole process of control of a company’s systems versions release, in addition to maintain and value by the organization of the whole process in production.

The Information Technology Infrastructure Library (ITIL) is a reference model for IT procedures management which its objective is to describe and to use a set of best management practices, thereby enabling the efficient and effective functioning of all services (MANSUR, 2005).

Based on the concept of best managing practices on ITIL, the shell is implemented with the objective of monitoring the check-list filled by valuator user. If the completion of check-list is reproved, an e-mail is sent informing all those involved that the process of release was reproved and the flow of approval is ended, sending the change to the necessary corrections. In the event of approval, shell triggers an e-mail to the auditor that will review the procedures quality carried out, concluding the liberation process. Shell is a file which keeps many controls that may be implemented when needed and are exactly the same the ones typed in the prompt (JARGAS, 2004, p. 2).

For the shell to proceed information approval or disapproval involved in the liberation process, is used the utilitarian UNIX cron system. Cron is a run process in UNIX and carries out controls in regularly scheduled crontab moments. The crontab is used to run scheduled programs with date and definite timetables (KOCHAN; WOOD, 1988, p. 239).

With this scenario the objective of this work is to present the development of a management tool for the liberation versions control based on the ITIL recommendation using UNIX Shell, controlling the flow of systems release to be approved by the customers. Furthermore, to provide reports with approved systems graphic information for the customers and the board. Ensure that all approved releases are stored in a secure manner and that such information is updated on a database. Implant flow procedures of releases management, ensuring that the software releases are tested and implemented correctly at the end of the approval.

2 INFORMATION TECHNOLOGY INFRASTRUCTURE LIBRARY

Information Technology Infrastructure Library (ITIL) is a model of best services practices of which methodology is to show do’s and don’ts, aiming at underlie the IT services supply, reaching better scores quality, mainly the activities of relationship with the client. This way, it strengthens the relationship between customer and IT area in accordance with the objectives agreed in advance by the Service Level Agreements (SLA) for the services provision (GRASSLAND, 2006).

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The ITIL is not a method, but offers a structure to plan the most common processes, roles and activities indicating the links between these and what lines of a communication are necessary. The ITIL is based on the need to provide high quality services, with an emphasis on the service and in the customer relationships, in other words, the organization has to meet customer requirements, which means good relationships with customers and suppliers (ITILFOUNDATION, 2006, p. 29).

The ITIL standards are documented in approximately 40 books that seek a set of best practice having the most comprehensive model for the best services of delivery for the support. The characteristics of ITIL are (ITILFOUNDATION, 2006, p. 29):

a) reference model for processes of IT no owner; b) suitable for all areas of activity; c) independent of technology and supplier; d) a real standard; e) based on best practices; f) a reference model for the implementation of procedures for IT; g) standardization of terminologies; h) interdependence of processes; i) basic guidelines for implementation; j) guidelines for basic functions and responsibilities within each process; k) examined and approved check-list; l) o’s and don’ts, that is, which must be done and what should not be done for the

work model’s success. The best practices are the best models of work identified in real situations

considering similar activities organizations, that is, means a model previously implemented, after determined and proven its relevance (MANSUR, 2005).

The ITIL is employed to define, monitor, measure and orientate incremental improvements on ‘support’ and ‘delivery’ of services in IT as can be seen in Image 1, that is, what is not defined may not be controlled, what is not controlled cannot be measured and that is not measured cannot be improved. The Service Support (SS) concentrates in day-to-day and to IT support services while the Service Delivery (SD) concentrates on the planning and improvement of services of IT (CAMEIRA; JESUS; KARRER, 2005, p. 13).

Image 1 - service management - ITIL Source: Cameira, R. F.; Jesus, L.; Karrer, D. (2005, p. 14).

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The ITIL is composed of processes that include the Service Management (SM). The SM therefore, together with the improvement in quality concepts perspective and services, having as main process the Service Support and Service Delivery (ITILFOUNDATION, 2006, p. 9).

2.1 THE CHANGE MANAGEMENT (CM)

Changes come up with the result of problems, but many of these may arise through pro-active attitudes that seek benefits as a reduction of costs or improvement of services. This process must be applied to use procedures and standardized methods, for the efficiently implementation of changes, and this way minimize the impact regarding service quality (ITILFOUNDATION, 2006, p. 74). Change Management is not responsible for identifying affected components in the field of Configuration Management, it is not responsible for identifying components which were amended on the field of Release Management (ITILFOUNDATION, 2006, p. 76).

Image 2 - Relationship of Change Managemet with other processes Source: Itilfoundation (2006, p. 79).

The process of Change Management includes the following activities

(ITILFOUNDATION, 2006, p. 76), as can be seen in Image 3: a) recording or Request For Change (RFC): although this activity is not carried out

by CM, it is its responsibility to certificate-that all the changes are being recorded correctly (ITILFOUNDATION, 2006, p. 78);

b) accepting or RFC approving: after the RFC registration, it must be assessed to be approved or rejected. All reproof must always be communicated explaining the reason for rejection and, once adopted, the RFC must be classified;

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c) classifying or RFC classification: after accepted and approved, the RFC shall be classified and its priority will be informed. The classification will depend on the impact caused by the change and the availability of necessary resources for the change completion;

d) RFC planning: the change will be planned and programmed by Forward Schedule of Change (FSC) carried out by Change Advisory Board (CAB) that meets to assess the impact of the change and to verify the availability of resources for its implementation (ITILFOUNDATION, 2006, p. 79);

e) coordination of activities: if approved by CAB, the change should be implemented, tested and executed. CM does not make this work, but coordinates the activities to ensure the progress of activities. CM will also verify whether the change was planned and submitted for approval;

f) change evaluating: each change, except minor changes, must be assessed to check if the desired effect was achieved. The effort of this evaluation shall dependent on the size of change and the impact in the organization, that is, carried out with success or not, what lessons can be learned.

Image 3 - Activities to include the Change Management process Source: Itilfoundation (2006, p. 77).

There must be a priority that defines the problem’s impact and the correction urgency

to each RFC. This priority is used to decide what changes should be discussed and assessed first. CM is responsible for giving such priority. It is important to decide the priority of a RFC

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with his creator, or if necessary, with the CAB. The risk evaluation is of crucial importance at the moment. The CAB will need information about the business consequences, to assess this change risk of implementation or not.

2.2 RELEASE MANAGEMENT (RM)

According to grassland (2006), the RM process is ‘responsible for planning and managing resources and means to test, release, distribute and implant changes (or updates) in an environment of operation/production, in a systemically and controlled form’. The RM is the process that ‘protects’ the production environment, or in other words, the protection comes in the formal proceedings form and extensive testing in respect of the proposed changes to the software or hardware within the environment of production (ITILFOUNDATION, 2006, p. 94). The RM has a holistic view of the change in the context of TI services of a company and shall ensure that all aspects of liberation, technical and not technical, shall be considered together, having the main focus on protecting the environment of production and their services, through the use of processes and formal checking. RM specific objectives are (CAMEIRA; JESUS; KARRER, 2005): to plan, to design and develop, to ensure, to communicate and manage, to ensure that the changes in software and hardware are implemented correctly, to ensure that all software original copies are stored securely and controlled in a Definitive Software Library (DSL) and that the Configuration Management Data Base (CMDB) is updated.

Image 4 illustrates some basic situations involving the process of implementing the RM, since its beginning until its end (GSTI, 2006, p. 55).

Image 4 - Activities to include the GM process Source: Gsti (2006, p. 55).

2.3 CONFIGURATION MANAGEMENT (CM)

The process of Configuration Management could almost be regarded as a pivot process for all other SS processes, per se; it is considered central and for supporting the other ITIL procedures providing information on the infra-structure (ITILFOUNDATION, 2006, p. 80). Is the Configuration Management’s responsibility to maintain CMDB. Populate the CMDB may be costly and lengthy depending on the infra-structure area that must be controlled.

Image 6 shows the relationships between the three processes and as outflows between the processes occur in each stage (ITILFOUNDATION, 2006, p. 85):

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Image 6 - Change Management Relationships with RM and CM. Source: Itilfoundation (2006, p. 85).

2.4 SHELL UNIX

UNIX presents the following resources and capacities (GLIESE, 1999): a) hundreds of utility programs to implement a wide variety of functions as creation,

editing, archives and text manipulation, the processing of controls and tasks, communication with other users, maintaining the system, and programs development;

b) shell commands interpreter, functioning as an interface with the user, it is a flexible tool that enables users to perform their work at the same time that provides a structure which separates and protects users and their environments one from the other and from the operational system as well;

c) archives system and entry and exit simplified system, where each archive, control, program and device for entry and exit is treated by operational system as a file that contains chains of characters;

d) UNIX was projected to be portable so that it can be implemented in several easily computational platforms;

e) once the UNIX was written in C programming language, it is easy to substitute special code modules by other more interesting for the system or to applications.

The UNIX system controls pattern interpreter is called shell which provides an abundance of characteristics, making it possible to specify very powerful controls (CHRISTIAN, 1985. p. 44).

The shell term is more usually used to refer to system programs like UNIX which may be used as a means of interaction between the user and the computer. Shell receptor interprets and shall implement the controls appearing on the screen as a line of command, represented by a prompt, anticipating the user controls (KOCHAN; WOOD, 2003).

Shell should be used whenever necessary (EUGENICAL; PALERMO, 2000, p.3 ): a complex procedure using many command lines; a procedure in which all users may be eligible; a simple command used several times; a task on a scheduled date; integrating information of several existing systems.

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The shell is an text archive which contains a sequence of instructions and controls, having as the main function, to interpret and translate a simple and friendly language for the user. Automatise routine tasks, as backup, installation or programs removal are some advantages on developing in shell (AMORIM, 2006). The implementation of the shell may or may not be scheduled through cron program.

For that programs can be performed periodically it is used a recorded table in the ‘/etc/crontab’ archive, which is responsible for scheduling the programs through the cron utilitarian. The cron utilitarian reads these archives and shall implement the programs as defined in the crontab archives (GROFF; WEINBERG, 1986, p. 106). The main parameters used in crontab are (PONIATOWSKI, 2003): -l user: to list the scheduled tasks for the user; -e user: edits the scheduler; -d user: erases the user filing; -c directory: specifies a directory for the crontab.

3 METHODOLOGY

The developed system aims to automate and manage the whole process of changes approval and releases for corrections of identified errors or requested amendments. To enable this automation process, it was studied the standard model of ITIL, its objectives and characteristics, mainly in the change management, release management and configuration management, making clear the whole work flow.

For the work specification, the following models were used: use cases diagrams, classes diagrams, states diagrams and diagrams of activities. For the use cases diagrams class preparation, of classes and of activities states, it was used the Enterprise Architect (EA) tool.

For the implementation were used the following techniques and tools: Unifield Modeling Language (UML), PHP, Shell, Enterprise Architect operational implementation.

Qualitative research explores the richness, depth, and complexity of phenomena. Qualitative research, broadly defined, means any kind of research that produces findings not arrived at by means of statistical procedures or other means of quantification (STRAUSS; CORBIN, 1990). So, the ultimate aim of qualitative research is to offer a perspective of a situation and provide well-written research reports that reflect the researcher's ability to illustrate or describe the corresponding phenomenon. One of the greatest strengths of the qualitative approach is the richness and depth of explorations and descriptions (MYERS, 2002).

4 RESULTS AND DISCUSSION

As a result, basically, the system has two distinct modules: the administration module which provides to the user a menu containing the screens with the system basic registers and the modulus of creation and controlling of a RFC approval flow.

The Liberation Management System (LMS) access screen is based on access profiles, or depending on the type of user who access, this forwards the same to different areas. If the user has an administrator profile, the same can access the screen with basic system’s register, for example: company’s database, areas, programs, version of the programs, users, types of users, critical nature, priorities, environments, check-list questions, liberation status, types of liberation and liberation process actions. These screens have basic features of insertion, editing and exclusion of records. The other users will need to participate in the register and flow of the process of change of RFC. If the user has a different profile of administrator, the same accesses the requirements screen which is aimed to list all pending documents and that are in the approval and release flow.

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The system also provides users an applications consultation screen allowing the user to run more detailed of RFC's created and released consultations. For the completion of a Request for Change (RFC), the system offers a screen whose main objective is to insert all the necessary information to be used during the process of liberation. The system also provides an attachments screen which allows the user to attach all documentation necessary for the approval procedure and change release.

After the completion of all the information and documentation, the system allows the user to direct RFC for the flow of approval and release where the main objective of the screen shall list the valuators and reviewers of RFC. After being sent to the flow of approval, the system allows the user to approve/reprove a process of change through screen approve/route, as illustrated in Image 7. This screen determines the continuity of RFC the flow of approval, in other words, defines if a RFC may or may not continue the process of change.

Image 7 - Approve/Forward RFC Screen Source: author.

During the process of change, the system offers a historic screen which objective is

to inform users throughout the history of RFC approval flow, that is, offers users all the way that a RFC come during this process. The Image 8 illustrates the main features of RFC historical screen.

Image 9 illustrates the screen of RFC check-list. The screen offers the check-list completing to the user the with the objective of approve/reprove the process of release or analyze the quality in the process of liberation. In accordance with the type of user connected to screen presents a different functionality, that is, if the user connected is the ‘valuator user’,

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the screen will provide to the very same the check-list completing so the release procedure can be approved or not and whether the connected user is the ‘RFC reviser’ the screen will provide to this one the check-list completing to be performed the quality of liberation process analysis.

Image 8 - RFC Historic screen Source: author.

Image 9 - RFC check-list screen Source: author.

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In accordance with the completion of check-list performed by valuator user, the system shall approve or not the process of liberation, that is, the screen has questions which the positive completion release procedure is approved. If one of these questions is answered negatively, the release process shall be rejected. In short, when the check-list is completed and the ‘valuator user’ saves this, the system will search it to approve or disapprove the liberation process. At this point, the shell which is scheduled in server’s Contrab to be 5 minutes will analyze the RFC status and in accordance to that, it will then send the e-mail to those involved in the liberation process. If the release procedure fails the shell will then send an e-mail to all those involved in the liberation process. If the release procedure is approved, the shell will then send an e-mail informing the RFC reviser, responsible for examining the liberation process quality.

One aspect in a managerial level, the system offers users the following reports and graphs which show information such as: situation per period, releases per period, type of releases and priorities per period.

The Image 10 illustrates the situation of the liberation process graph during a given period. The same can illustrate a graph with all its pre-defined status in the developed system.

Image 10 - Statistical Releases Report performed by period Source: author.

The RFC's registration may be performed in two ways: in paper or electronic format,

through a management software service of IT. With the objective to have a greater reliability and safety as regards the handling of extremely important information and with the objective to store the historical process of registration, approval and release of changes was decided to apply a solution automating the concept based on ITIL recommendation.

The system has developed the concepts of Change Management, Release Management and a brief concept of Configuration Management in governing the recommendation of ITIL. While the Change Management ensures that all the implementations

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and changes in IT infra-structure are analyzed and planned so it has the lowest risk and impact (GSTI, 2006, p. 48), the Release Management focuses in protecting the production environment and their services through the use of processes and formal checking (ITILFOUNDATION, 2006, p. 90). On the other hand the Configuration Management seeks to maintain a record of all active ICs within the IT infra-structure in addition to certify that all the releases are being stored in DSL and/or DHS (GSTI, 2006, p. 63). Based on these concepts it was pursued all the understanding of the model to which could define the requirements and business rules of the proposed system. It is important that the Configuration Management concept has a more theoretical than a practical focus, that is, it is only used for the impact on infra-structure analysis of a customer only when a requisition is asked for the JCC/EC profile approval.

For being a new concept presenting some bureaucratic complexity in governing the implementation of business processes, the developed system focuses primarily on the concept of Change Management which seeks to control and register, filter and prioritize the changes approval in infra-structure, thus reducing the negative impact so that a service is unavailable due to flaws in its implementation.

As for the Release Management, the system seeks to protect the environment to the implementation of change to be made through formal procedures or extensive tests, in addition to the documentation and training carried out with the technical and user’s keys. However, it will depend on the involvement of each one to run the tests and validate throughout the environment and then submit the liberation process for the next step of approval. In short, the proposed system only registers that there was the validation, approval and training, but does not have an automatic process ensuring that the validation and training of those involved in this process have actually been done.

On the concept of Configuration Management, it may be said that the system uses only a brief concept of the discipline. In short, the system retains all the historic of all records and the changes implementations approvals ran or not. The implemented system could have elaborated more this discipline, but it would change the original proposal scope, in which was proposed the implementation of a management system with the objective of controlling the approval flow and release of changes to be carried out. Another justification would be by virtue of not been able to implement the whole discipline concept, weakening the system on what concerns the release and change management.

The search for a free distribution of the not found UNIX operational system for the implementation of the shell was one of the change factors faced during the process of work defining. However, it was managed to be found the free distribution of Fedora Core 6 LINUX operational system for the requirement compliance of shell implementation.

The use of implemented shell via LINUX operational system could be exempted for implementation of API JavaMail which is used for sending e-mails with the objective of communicate everyone on any reported action during the approval flow. API JavaMail is used for reading and sending e-mails and offers several essential resources for corporate applications, among which is highlighted: support for various dispatch and reading e-mail protocols, for example, POP3, SMTP and IMAP; support for HTML messages; support for sending e-mails with attachments (ZUKOWSKI, 2007).

5 CONCLUSONS

Considering that the majority of problems related to the quality of services is normally related to some badly made change, without planning of appropriate tests and an increasingly number of users requiring highest service levels to reach business goals, the developed system aims to control and automate the process of releases. To reach these levels

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of quality services and to monitor this process, it is primarily used the ITIL recommendation the concepts of practical planning of Change Management and Release Management and a brief concept of Configuration Management, which focuses on a more theoretical concept of management, only analyzing the impact on the customer infra-structure where a change is suggested.

This work aggregates the perception of supply competitive differentials to customers in order to expedite the process of releases, controlling all the changes in an orderly way, through a flow of approval, which ensures greater reliability and safety as regards the impact of business, because it maintains a history of whom, when and where these were implemented.

In relation to the proposed objectives at the beginning of this work, it may be said that all were achieved. During the development, it was realized that it reaches its main objective which is to manage the flow of approval and liberation, thus ensuring that all the changes to be implemented will be stored in a secure manner in a database, in addition to being tested and implemented protecting the environment of production. Another achieved objective was the provision of reports, represented by managerial listings or graphics, allowing a historical information on all the releases performed by facilitating communication with the customer in addition to expedite the process of seeking information during a given period.

The use of shell implemented during the development of the system has the objective to monitor the check-list manned by valuator user. If filling fails, the shell will shoot an e-mail to all involved with the objective to inform that the process of release was reprobated, ending the approval flow sending change to the necessary corrections. If the completion of check-list is approved, the shell will shoot an e-mail to the auditor with the objective of the same assess the quality of the liberation process. The process of liberation is finalized after this assessment.

The greatest ITIL model advantage of use is in the fact that it is not necessary to reinvent techniques and, on the other hand to adopt and adapt already tested techniques which provide time gain in addition to faster feedback in the implementation process of management services.

At the end of this work, it was reached the conclusion that ITIL model is somewhat bureaucratic, but if it is properly used, may be achieved high levels of quality in the provision of IT services. For this, it is necessary that there is a change in culture and a commitment by all involved, avoiding that there are forms of cod process.

The developed system in this work has some limitations as it does not possess an available resource for the chosen user amendment in the process of approval, if the same is on holidays or is not any longer part of the organization.

When a RFC is in emergency character, the e-mails sending also becomes a limitation of the system when there is a delay due to problems in infra-structure or when the users are not checking out their e-mails in their work station. Another limitation of the system is not holding a full report with the configuration management, on what is related to the active configuration items in the customer’s infra-structure, as regards the impact analysis of implementation even before the RFC be forward to the approval process.

The presented work aims to manage the changes approvals flow based on ITIL recommendation. The ITIL management used during the development shall ensure that every single change performed in the liberation process must go through an approval and release process guaranteeing the least possible impact of implementations in a production environment. Thus, it is suggested this work’s new extensions, the implementations of other functions as: to implement a resource of Case Base Reasoning (RBC) warning the RFC

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creator about releases with the previously same applied scope, presenting divergent points which occur during the for new RFC release procedure; to develop a resource which shall be recorded all active configuration items, implementing a change management concept as a whole, with the objective of evaluating the impact of liberation even before the RFC go to the approval process; to develop a routine of sending SMS messages to involved users in the release process, to inform the change approval or rejection.

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