strace is a handy utility for tracing system, file, and network calls on a Linux system. It can produce trace output for either an already running process, or it can create a new process.
Some of the most common troubleshooting scenarios are needing to isolate either the network or file system activity of a process. For example to determine whether an application was attempting to reaching out to a server on the expected port, or to understand why a startup configuration file was not being read from the expected directory.
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The prevalence of the long chains of firewall and reverse proxy solutions present in production infrastructure (and made even more popular with the dynamic routing introduced with containers) has made analysis of the end-user side of the network exchange a critical tool in troubleshooting.
Fiddler has long been a solid tool for both proxy capture as well as analysis of the end user application traffic on the Windows platform. However, troubleshooting issues with customers always required them to first install the tool on their desktop, and at times corporate policies would prevent installation.
Now, with the built-in capabilities of the Chrome DevTools and Firefox Network Monitor, the capture can happen directly from the end user’s browser without any external tool installation. If that session needs to be analyzed by higher level support resources, it can be exported as an HTTP Archive (HAR), and then imported into Fiddler for analysis at a later time.
And since the release of Fiddler for Linux, the analysis of the HAR can be done directly on the Ubuntu desktop.
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