^ Flag           ^ Description                                                        |       
| -I, --head     | Fetch the HTTP-header only                                         |    
| -v, --verbose  | Fetching is more talkative. Used for debugging                     |   
| -s, --silent   | Silent or Quiet (Mute). Don't show progress meter or error messages|  
| -i, --include  | Header plus content                                                |
| -X , --request | Specify a customer request when communicating with HTTP web server |
| -L,            | Follow the redirect                                                |
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__**Troubleshooting a website**__. You can replace http://website.com with http://localhost if you wish to test the domain on the local machine
<sxh bash>
curl -LIX GET 12.34.56.78 -H 'Host: example.com'
</sxh>
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The following command is used to test a https domain. -k will skip the certificate check
<sxh bash>
curl -LIkX GET https://website.com
</sxh>
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**__Testing a vhost on the localhost__**
<sxh bash>
curl -LIvX GET localhost -H 'Host: vhost.com'
</sxh>
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**__Body String Match__**
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<sxh bash>
curl -sLX GET www.lukeslinux.co.uk | grep -i lukeslinux
</sxh>
<sxh bash>
curl -isX GET lukeslinux.co.uk | grep Maintenance
</sxh>
Output:
<sxh bash>
<title>Days Out With Kids | Maintenance</title>
                                    <h3>Sorry, Site Under Maintenance</h3>
</sxh>
Example without the s flag
<sxh bash>
curl -LiX GET https://tickets.daysoutwithkids.co.uk/longleat | grep Maintenance 
</sxh>
Output:
<sxh bash>
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  9885  100  9885    0     0   280k      0 --:--:-- --:--:-- --:--:-- 9653k
        <title>Days Out With Kids | Maintenance</title>
                                    <h3>Sorry, Site Under Maintenance</h3>
</sxh>
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Curling localhost and ignoring ssl
If the website has an ssl certificate you can also apply the 'k' option to bypass the certificate check. e.g:
<sxh bash>
curl -ikL localhost -H 'https://website.com' | grep body_match_string
</sxh>
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**__Time__**
<sxh bash>
time for i in {1..10}; do curl -IsX GET http://example.co.uk | grep 'HTTP/1.1'; done
</sxh>
**__Using Lynx__**
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Note: This is not as accurate as curl
Testing to see if a website returns a certain string. Body match strings are often used in monitoring alerts
<sxh bash>
lynx -dump http://lukeslinuxlessons.co.uk | grep 'string match'
</sxh>
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=== Time to First Byte ===
Make sure you replace x.x.x.x with the server IP and Host: Example.com with the website
<sxh bash>
curl -sko /dev/null -w "\ncontent_type=%{content_type}\nhttp_code=%{http_code}\nsize_download=%{size_download}\nsize_header=%{size_header}\nsize_request=%{size_request}\nspeed_download=%{speed_download}\ntime_connect=%{time_connect}\ntime_namelookup=%{time_namelookup}\ntime_pretransfer=%{time_pretransfer}\ntime_redirect=%{time_redirect}\ntime_starttransfer=%{time_starttransfer}\ntime_total=%{time_total}\nurl_effective=%{url_effective}\n\n" -H "Host: example.com" http://x.x.x.x
</sxh>

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__**HTTP AUTHENTICATION**__
<sxh bash>
curl --user luke:password http://lukeslinux.co.uk/secret
</sxh>