Bug 1303424

Summary: Verifying the Downloaded Image on Windows
Product: [Fedora] Fedora Documentation Reporter: Jakub Jelen <jjelen>
Component: install-guideAssignee: Clayton Spicer <cspicer>
Status: CLOSED DUPLICATE QA Contact: Fedora Docs QA <docs-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: develCC: mattdm, pbokoc, zach
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OS: Unspecified   
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Fixed In Version: Doc Type: Bug Fix
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Last Closed: 2016-02-03 13:09:43 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Jakub Jelen 2016-01-31 17:03:23 UTC 
Description of problem:
Current guide proposes PowerShell script to verify checksum under windows, that requires to load the whole image into the memory. This is not ideal and might fail on systems with less RAM.

Version-Release number of selected component (if applicable):
fc23 so far

How reproducible:
on systems with not-enough available RAM

Steps to Reproduce:
1. run proposed commands from guide [1]

Actual results:
this might fail:

    $download_checksum = [System.BitConverter]::ToString($sha256.ComputeHash([System.IO.File]::ReadAllBytes("$PWD\$image"))).ToLower() -replace '-', ''


Expected results:
should work more effective:

    $stream = (Get-Item $filename).OpenRead()
    $hash = $sha256.ComputeHash($stream)
    $stream.Close()
    $download_checksum = [BitConverter]::ToString($hash).ToLower() -replace '-'

Source [2] with license:
 under cc by-sa 3.0 with attribution required


Additional info:
[1] https://docs.fedoraproject.org/en-US/Fedora/23/html/Installation_Guide/sect-verifying-images.html
[2] http://stackoverflow.com/a/35116369/2196426
Comment 1 Matthew Miller 2016-02-03 13:09:43 UTC 

*** This bug has been marked as a duplicate of bug 1175759 ***