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 Overview Serverless applications don’t require you to provision, scale, and manage any servers. You can build them for nearly any type of application or backend service, and everything required to run and scale your application with high availability is handled for you. Serverless architectures can be used for many types of applications. For example, you can process transaction orders, analyze click streams, clean data, generate metrics, filter logs, analyze social media, or perform IoT device data telemetry and metering. In this project, you’ll learn how to build a serverless app to process real-time data streams. You’ll build infrastructure for a fictional ride-sharing company. In this case, you will enable operations personnel at a fictional Wild Rydes headquarters to monitor the health and status of their unicorn fleet. Each unicorn is equipped with a sensor that reports its location and vital signs. You’ll use AWS to build applications to process and visualize ...

A process is a running instance of a launched, executable program. A process consists of: an address space of allocated memory, security properties including ownership credentials and privileges, one or more execution threads of program code, and the process state. The environment of a process includes: local and global variables, a current scheduling context, and allocated system resources, such as file descriptors and network ports. An existing ( parent ) process duplicates its own address space ( fork ) to create a new ( child ) process structure. Every new process is assigned a unique process ID (PID) for trackin...

The setuid permission on an executable file means that the command will run as the user owning the file, not as the user that ran the command. One example is the passwd command: [student@desktopX ~]$ ls -l /usr/bin/passwd -rw s r-xr-x. 1 root root 35504 Jul 16 2010 /usr/bin/passwd In a long listing, you can spot the setuid permissions by a lowercase s where you would normally expect the x (owner execute permissions) to be. If the owner does not have execute permissions, this will be replaced by an uppercase S . The special permission setgid on a directory means that files created in the directory will inherit their group ownership from the directory, rather than inheriting it from the creating user. This is commonly used on group collaborative directories to automatically change a file from the default private group to the shared group, or if files in a directory should be...

The command used to change permissions from the command line is chmod , short for "change mode" (permissions are also called the mode of a file). The chmod command takes a permission instruction followed by a list of files or directories to change. The permission instruction can be issued either symbolically (the symbolic method) or numerically (the numeric method). Symbolic Method Keywords chmod WhoWhatWhich file|directory Who is u, g, o, a (for user, group, other, all) What is +, -, = (for add, remove, set exactly) Which is r, w, x (for read, write, execute) The symbolic method of changing file permissions uses letters to represent the different groups of permissions: u for user, g for group, o for other, and a for all. With the symbolic method, it is not necessary to set a complete new group of permissions. Instead, it is possibl...

Access to files by users are controlled by file permissions . The Linux file permissions system is simple but flexible, which makes it easy to understand and apply, yet able to handle most normal permission cases easily. Files have just three categories of user to which permissions apply. The file is owned by a user , normally the one who created the file. The file is also owned by a single group , usually the primary group of the user who created the file, but this can be changed. Different permissions can be set for the owning user, the owning group, and for all other users on the system that are not the user or a member of the owning group. The most specific permissions apply. So, user permissions override group permissions, which override other permissions. In the graphic that follows, joshua is a member of the groups joshua and web, while allison is a member of allison, wheel, and web. Whe...