title: Pip ProxyError Cannot connect to proxy on CentOS Linux release 7.9.2009
body: <p>I'm having trouble installing libraries using pip in my freshly installed CentOS 7 (7.9.2009) server.</p>
  <p>I installed python 3.8.3 and upgrade the pip right away to the latest version 21.0.1.</p>
  <p>Already exported my <code>http_proxy</code> and <code>https_proxy settings</code>,</p>
  <pre><code>http_proxy=http://&lt;creds&gt;@10.XXX.XX.XX:XXX
  https_proxy=https://&lt;creds&gt;@10.XXX.XX.XX:XXX 
  </code></pre>
  <p>But when I try to install libraries via pip I get this error.</p>
  <pre><code>[root@localhost downloads]# pip3.8 install pandas --proxy https://user:pwd@10.XXX.XXX.XXX:808
  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', timeout('_ssl.c:1091: The handshake operation timed out'))': /simple/pandas/
  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', timeout('_ssl.c:1091: The handshake operation timed out'))': /simple/pandas/
  WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', timeout('_ssl.c:1091: The handshake operation timed out'))': /simple/pandas/
  WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', timeout('_ssl.c:1091: The handshake operation timed out'))': /simple/pandas/
  WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', timeout('_ssl.c:1091: The handshake operation timed out'))': /simple/pandas/
  ERROR: Could not find a version that satisfies the requirement pandas
  ERROR: No matching distribution found for pandas
  </code></pre>
  <p>I tried the verbose mode to check.</p>
  <p><a href="https://i.stack.imgur.com/cLwmq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cLwmq.png" alt="verbose pip error" /></a></p>
  <p>I tried to check tha pandas url via curl if i can access it, and yes I can.</p>
  <pre><code>[root@localhost downloads]# curl -I https://pypi.org/simple/pandas/
  HTTP/1.1 200 Connection established
  Proxy-agent: CCProxy
  
  HTTP/1.1 200 OK
  Connection: keep-alive
  Content-Length: 381742
  Cache-Control: max-age=600, public
  Content-Security-Policy: default-src 'none'; sandbox allow-top-navigation
  Content-Type: text/html; charset=UTF-8
  ETag: &quot;zPB5FsC5JkZZm1ZnKHnuUw&quot;
  Referrer-Policy: origin-when-cross-origin
  Server: nginx/1.13.9
  X-PyPI-Last-Serial: 9182431
  Accept-Ranges: bytes
  Date: Wed, 03 Feb 2021 07:44:51 GMT
  X-Served-By: cache-bwi5146-BWI, cache-sin18034-SIN
  X-Cache: HIT, HIT
  X-Cache-Hits: 1, 1
  X-Timer: S1612338291.161041,VS0,VE1
  Vary: Accept-Encoding, Accept-Encoding
  Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  X-Frame-Options: deny
  X-XSS-Protection: 1; mode=block
  X-Content-Type-Options: nosniff
  X-Permitted-Cross-Domain-Policies: none
  </code></pre>
  <p>I also tried to <code>wget</code> the latest pandas file in the said repository and I was able to download it.</p>
  <pre><code>[root@localhost downloads]# wget https://files.pythonhosted.org/packages/11/1c/b0bc154996617eae877ff267fcf84e55e6c6808dbade0da206f0419dd483/pandas-1.2.1.tar.gz#sha256=5527c5475d955c0bc9689c56865aaa2a7b13c504d6c44f0aadbf57b565af5ebd
  --2021-02-03 10:47:24--  https://files.pythonhosted.org/packages/11/1c/b0bc154996617eae877ff267fcf84e55e6c6808dbade0da206f0419dd483/pandas-1.2.1.tar.gz
  Connecting to 10.XXX.XXX.XXX:808... connected.
  Proxy request sent, awaiting response... 200 OK
  Length: 5459053 (5.2M) [application/x-tar]
  Saving to: ‘pandas-1.2.1.tar.gz’
  
  100%[============================================================================================&gt;] 5,459,053    418KB/s   in 13s
  
  2021-02-03 10:47:39 (399 KB/s) - ‘pandas-1.2.1.tar.gz’ saved [5459053/5459053]
  </code></pre>
  <p>Am I missing something here? Im thinking of server setting that is causing this. Or is it just the proxy is not working?</p>