ADMIN Network & Security的November/December 2024目录

I first wrote about job burnout five years ago in 2019 [1]. I offered some valid advice, and the bottom line was, “Work to live rather than live to work.” This advice still stands. Compartmentalizing your life preserves your mental and physical health, but it’s not enough, and five years later, I’ve realized the shortcomings of that simplistic analysis. Burnout is far more complex than I ever imagined and dealing with it alone has given me new insights that I hope will also help you. Burnout has many origins: stress, repetitive tasks, the feeling of no end in sight, the need to keep your technical skills sharp, negative feedback, no feedback, low or no salary incentives, no job ladder or promotions, and the feeling that people see you as a…

The MongoDB document database stores structured or unstructured data in a JSON-style format that can be mapped directly to native objects in most modern programming languages. It offers developers a modicum of convenience because they don’t need to worry about normalizing data. MongoDB is also a good choice for large volumes of data and scales both vertically and horizontally. The company behind the database, MongoDB Inc., was founded in 2007 with the aim to develop a modern database that meets the requirements of agile, scalable applications. The first version was launched in 2009, and the database has seen continuous improvements and extensions ever since. Milestones include functions such as sharding for horizontal scaling, replica sets for high availability, and the on-going advancement of query functions and proprietary tools. Variants MongoDB…

Centralized storage in the form of network-attached storage (NAS) or a storage area network (SAN) are implicitly or explicitly set in stone in the data center. Wherever you look, you will likely find a device whose sole task it is to provide persistent storage to the other systems. From the administrator’s point of view, it makes sense to handle central tasks such as redundancy and backup with a single point of administration. The alternative would be uncontrolled local growth with complicated backup and redundancy mechanisms. Of course, local storage is occasionally inevitable (e.g., in cloud setups where virtual machines require extremely fast storage). However, cloud providers tend to assume that the customer’s application takes care of data redundancy and regular backups itself. For almost all other scenarios, centralized storage is…

The Internet small computer systems interface (iSCSI) [1] is a block-level [2] interfacing protocol used in conjunction with any network-attached storage (NAS) unit. As the name implies, iSCSI uses the locally focused SCSI block storage protocol and adds the ability to reference resources across the network. By issuing SCSI commands over the TCP/ IP suite, iSCSI makes it possible to integrate a remote mount-point located anywhere on the Internet, including in another time zone. The iSCSI protocol essentially lets you treat remote storage as if it were local. In other words, you can set up a storage area network (SAN) with existing resources – and without a lot of expensive equipment. The iSCSI bus is a good fit for heavy read and write scenarios (e.g., high-availability (HA) environments). Even though…

Admins often face the challenge of meeting dynamic requirements. Although the trend is toward cloud-native applications and microservices – as seen primarily in the form of large numbers of comparatively small virtual machines (aka container hosts) – some applications still require massive, performance-hungry virtual machines (VMs, e.g., SAP HANA, an in-memory, column-oriented relational database management system). These monster VMs require proper handling. Running large, resource-hungry, and monolithic applications such as Oracle, Microsoft SQL, and especially SAP HANA successfully on VMware vSphere is challenging, because they have many more factors to consider than do smaller VMs. Many of the configuration best practices mentioned in this article originate from the SAP HANA environment but are just as useful for other monster VMs and their applications. An in-depth report would go beyond the…

The everything-as-code trend is popular in IT today. The complete hardware and software configuration is stored in text files, and an automation tool rolls everything out. Fortunately, arcane file formats (e.g., sendmail.cf) are pretty much a thing of the past; instead, you can expect easily readable formats such as YAML and perhaps JSON. The information in these files can usually be converted into one of the other formats without loss. YAML is the preferred format of the Ansible automation tool, which is used here for as-code automation. Thanks to its modular structure, Ansible can control pretty much everything in the data center and the cloud, including rolling itself out from its command line. This scenario might sound strange, but in the automation-as-code example, it makes sense to roll out a…

Open Source AI Definition Now Available Version 1.0 of the Open Source AI Definition (OSAID – https://opensource.org/ai) is now available. The definition, which was developed through a year-long, global, community process led by the Open Source Initiative (OSI – https://opensource.org/), defines an Open Source AI as “an AI system made available under terms and in a way that grant the freedoms to”: • Use the system for any purpose and without having to ask for permission.• Study how the system works and inspect its components.• Modify the system for any purpose, including to change its output.• Share the system for others to use with or without modifications, for any purpose. The OSAID “offers a standard by which community-led, open and public evaluations will be conducted to validate whether or not…

Vector databases store data in a numerical format as vectors. If you look at an arbitrary group of words, such as “A blue striped cotton shirt,” the vector mapping would look something like: This numerical expression contains the coordinates of the words in a multidimensional space. When a sentence, an image, or a video is converted into a vector, the numerical values stand for the meaning of the statement in question. In the example, the vectors of the word groups “A blue striped cotton shirt” and “A nautical cotton shirt” would point to locations close to each other in multidimensional space. The interesting thing here is that the vector database’s search algorithm processes the query and computes the distance between the two vectors that are connected in this way by…

In the old days, before virtualization was practical, if you wanted to run a service, you installed an operating system (OS) on a physical machine and then manually installed the service. If more than one instance of the OS was required, you needed to purchase additional computers and repeat the process manually. As you might imagine, administering a large fleet of computers this way is unworkable in the long run, so automation tools were created. Fully Automatic Installation (FAI) [1] is a good example of an early, generic tool for deploying Linux distributions over a sizable number of machines. Tools such as FAI created for physical machines are of use when deploying virtual machines, as well, as are distro-specific tools (e.g., autoinstall for OpenBSD [2], preseed for Debian [3], Kickstart…

Advanced Intrusion Detection Environment (AIDE) uses various techniques to detect the manipulation of files, starting with regular expressions for selecting the files to be included in the integrity checks. The files are then processed with hashing tools to generate checksums. Additionally, the associated filesystem properties, such as access rights, inodes, SELinux, Amazon Elastic File System (EFS), and other extended attributes, are also taken into account. Setup and Use To use AIDE for integrity checks, you first need to install the tool with your distribution’s package manager. AIDE is included in all the popular distributions; if your environment is not supported, you can easily download the release from the GitHub project [1]. After the install, launch AIDE directly; you will need to be root, use sudo, or launch a root shell.…

Anyone who uses Git will quickly see the true value of version management. I have set up my own Git server with all kinds of features on a Raspberry Pi with the Gogs self-hosted Git service software, but as of now, the Gogs repository has had very little activity, with releases only appearing every six months and offering very little in terms of new features. This situation led me to believe that the software will probably not survive much longer. Unfortunately, I didn’t realize the unhealthy state of Gogs until I was already dealing with versions that have no easy migration path to Gitea, a fork of Gogs and the new home I chose for my code. The two projects have drifted apart since the fork. In this article, I…

The Raspberry Pi 5 added a new port for a flexible printed cable (FPC) exposing PCI Express (PCIe) for the first time in the history of the beloved single-board computer (SBC; Figure 1). Eclipsed by the convenience of the equally new and faster USB 3.0 ports that now support simultaneous 5Gbps operation and a much improved high-speed microSD card interface, you can understand the Foundation’s lack of urgency in delivering an expansion board to add PCIe storage to the lineup. However, the wait is finally over, and you can now assess the full set of new storage options available to Pi users. M.2 Expansion With new silicon, last year the Pi 5 delivered close to three times the CPU and GPU performance and twice the memory and I/ O bandwidth…

To remain competitive, companies in all sectors need to incorporate the principle of data-driven decisions into their business logic, bearing in mind that data growth, especially the growth of unstructured data, is omnipresent. Market research institutes assume significant growth rates in the global market for data-driven artificial intelligence (AI). AI helps structure and manage the flood of data in a meaningful way – not just in large corporations, but also in small and medium-sized enterprises (SMEs). Well-designed AI-based applications rapidly search through even the largest of datasets to gain new insights and ultimately open new business models capable of generating real added value for companies. The World of Complex Data Against the background of these challenges, vector databases open a new category of database management and a paradigm shift in…

Viewed at an abstract level, very much of what is known revolves around the relationship of two or more things to each other: events to dates, nuclear charges to chemical properties, items to prices, authors to works, and so on. Rows and columns in a table are an obvious way of mapping these relationships. The ancient Greeks were literally already aware of this advantage – Ptolemy started recording astronomical observations in tabular form in the second century. Since then, the table has triumphed in all areas of life, from religion, where the description of the same events in different gospels was recorded in tabular form centuries ago (canon tables), to music, where musical notation can be understood as a table in which the bar lines mark the columns and the…

Atlassian Confluence is a popular collaboration platform used by many organizations around the world. Users are accustomed to relying on Confluence for meetings, memos, wikis, and project management; however, Atlassian recently announced that they are discontinuing the server edition in favor of a cloud-only configuration. Many customers with sensitive information, such as research companies in the high-tech industry, lawyers, financial service providers, and journalists, are concerned about moving all their collaboration data to the web. Others, even if they aren’t in particularly sensitive industries, might not want to give their data to the cloud for any number of policy or practical reasons. Even as some Confluence admins grapple with the challenge of moving to the Atlassian cloud, others are looking for alternatives that will let them keep their data local…

Replication of local databases to the cloud offers many benefits, including improved availability: Databases in the cloud keep working even if the local SQL Server fails. Many companies also rely on this function to ensure smooth migration of SQL databases to the cloud, which means local SQL servers can ultimately be retired. Organizations that operate their own SQL servers need to choose the best possible hardware to keep the database servers running efficiently. With requirements for database servers constantly growing, licenses becoming increasingly expensive, and numerous services requiring data from your servers for their own operations, you have reason enough to outsource databases or entire database servers to the cloud. Replication with Azure SQL can be a simple approach, because as soon as all the data has been transferred, the…

When it comes to structured data storage, admins have viewed relational databases such as MySQL or PostgreSQL to be the ideal solution for decades. No other tool can store large volumes of data in such an efficient way, and virtually no other language can access databases as well as the powerful and versatile SQL. In the meantime, relational databases have become so popular that the top players in this genre have virtually become generic terms for databases themselves, to which the LAMP stack (e.g., Linux, Apache, PHP, MySQL) bears witness to this day. However, just as LAMP has become less important over the years, the hype surrounding relational databases has died down, at least a little, for understandable reasons: The complexity of a relational database is by no means helpful…