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Common Problems 117516

Ubuntu 20.04 DNS Resolution Fails Intermittently

🟡 Medium   ⏱ 5–30 min  Last verified: 27 July 2021 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

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How to Set Up FreeNAS-style ZFS on FreeBSD 12 — step-by-step FreeBSD 12 tutorial on Progressive Robot

How to Set Up FreeNAS-style ZFS on FreeBSD 12

Introduction This guide explains how to Set Up FreeNAS-style ZFS on FreeBSD 12 on FreeBSD 12. FreeBSD uses the pkg(8) binary package manager, rc.conf(5) for service startup configuration, and pf(4) as its primary packet filter. There is no SELinux or AppArmor — instead, FreeBSD provides the MAC (Mandatory Access Control) framework and Capsicum for fine-grained […]

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FreeBSD 13 — apache+mod_ssl+mod_snmp+mod_accel+mod_deflate+ipv — multiple vulnerabilities (3 CVEs) — patch and remediation guide — diagnosis and fix on FreeBSD 13

FreeBSD 13 — apache+mod_ssl+mod_snmp+mod_accel+mod_deflate+ipv — multiple vulnerabilities (3 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 27 July 2021 Affected versions: FreeBSD 13 📖 ~4 min read  •  Source: FreeBSD VuXML VuXML topic: apache — Prevent chunk-size integer overflow on platforms where sizeof(int) < sizeof(long) Related CVEs: CVE-2005-2088 CVE-2005-3352 CVE-2006-3747 Upstream summary: Apache ChangeLog reports: Integer overflow in the ap_proxy_send_fb function in proxy/proxy_util.c […]

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Java FileWriter Example — step-by-step Programming tutorial on Progressive Robot

Java FileWriter Example

URL: https://www.progressiverobot.com/java-filewriter-example/ Java FileWriter Java FileWriter class is a part of java.io package. FileWriter is a sub class of java.io.OutputStreamWriter class. FileWriter is meant for writing streams of characters. FileWriter is used to write to character files. Its write() methods allow you to write character(s) or strings to a file. FileWriters are usually wrapped by […]

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AlmaLinux 8 — spice-vdagent — multiple vulnerabilities (4 CVEs) — patch and remediation guide — diagnosis and fix on AlmaLinux 8

AlmaLinux 8 — spice-vdagent — multiple vulnerabilities (4 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: AlmaLinux 8 📖 ~4 min read  •  Source: AlmaLinux ALSA ALSA-2021:1791 Related CVEs: CVE-2020-25650 CVE-2020-25651 CVE-2020-25652 CVE-2020-25653 Upstream summary: The spice-vdagent packages provide a SPICE agent for Linux guests. Security Fix(es): * spice-vdagent: possible file transfer DoS and information leak via active_xfers […]

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FreeBSD 13 — py36-pyrad — multiple vulnerabilities (2 CVEs) — patch and remediation guide — diagnosis and fix on FreeBSD 13

FreeBSD 13 — py36-pyrad — multiple vulnerabilities (2 CVEs) — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 27 July 2021 Affected versions: FreeBSD 13 📖 ~4 min read  •  Source: FreeBSD VuXML VuXML topic: pyrad — multiple vulnerabilities Related CVEs: CVE-2013-0294 CVE-2013-0342 Upstream summary: Nathaniel McCallum reports: packet.py in pyrad before 2.1 uses weak random numbers to generate RADIUS authenticators and hash passwords, which […]

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How To Validate a Login Form With React and Formik — step-by-step Javascript tutorial on Progressive Robot

How To Validate a Login Form With React and Formik

In order to ensure that the form element of your web application is returning valid data, it is helpful to build automated validation into your code. This is true in React as well; creating form validation early on can often save you from encountering errors down the road. In this tutorial, you will create a React project, add the Formik package, customize the Formik component with an onSubmit callback and a validate function for error messages, then display those error messages to the user.

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FreeBSD 12 — opensearch — multiple vulnerabilities (3 CVEs) — patch and remediation guide — diagnosis and fix on FreeBSD 12

FreeBSD 12 — opensearch — multiple vulnerabilities (3 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 27 July 2021 Affected versions: FreeBSD 12 📖 ~4 min read  •  Source: FreeBSD VuXML VuXML topic: OpenSearch — Log4Shell Related CVEs: CVE-2021-44228 CVE-2021-45046 CVE-2021-45105 Upstream summary: OpenSearch reports: CVE-2021-45105 for Log4j was issued after the release of OpenSearch 1.2.2. This CVE advises upgrading to Log4j 2.17.0. […]

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How To Test a React App with Jest and React Testing Library — step-by-step Javascript tutorial on Progressive Robot

How To Test a React App with Jest and React Testing Library

Obtaining solid test coverage is imperative for building confidence in your web application. In this tutorial, you will test asynchronous code and interactions in a sample project containing various UI elements. You will use Jest to write and run unit tests, and you will implement React Testing Library as a helper DOM library to handle interacting with components.

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