My work uses an NTLM proxy. On my Linux servers and workstations we us cntlm to authenticate. I'm not having any issues with yum,wget, or the web browser, but for some reason curl refuses to work correctly.

[root@rhel7 ~]# curl -vv https://get.docker.com/
* About to connect() to get.docker.com port 443 (#0)
*   Trying
* Connected to get.docker.com ( port 443 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
*   CAfile: /etc/pki/tls/certs/ca-bundle.crt
CApath: none
* NSS error -5938 (PR_END_OF_FILE_ERROR)
* Encountered end of file
* Closing connection 0
curl: (35) Encountered end of file

Here is my version information:

[root@rhel7 ~]# curl -V -v
curl 7.29.0 (x86_64-redhat-linux-gnu) libcurl/7.29.0 NSS/ 
Basic  ECC zlib/1.2.7 libidn/1.28 libssh2/1.4.3
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps 
pop3 pop3s rtsp scp sftp smtp smtps telnet tftp 
Features: AsynchDNS GSS-Negotiate IDN IPv6 Largefile NTLM NTLM_WB SSL libz 

Of course, it works if I connect to localhost:

[root@rhel7 ~]# curl -vv localhost/mediawiki/
* About to connect() to proxy port 3128 (#0)
*   Trying
* Connected to ( port 3128 (#0)
> GET HTTP://localhost/mediawiki/ HTTP/1.1
> User-Agent: curl/7.29.0
> Host: localhost
> Accept: */*
> Proxy-Connection: Keep-Alive
< HTTP/1.1 301 Moved Permanently
< Date: Mon, 01 Feb 2016 19:43:50 GMT
< Server: Apache/2.4.6 (Red Hat Enterprise Linux) PHP/5.4.16
< X-Powered-By: PHP/5.4.16
< X-Content-Type-Options: nosniff
< Vary: Accept-Encoding,Cookie
< Expires: Thu, 01 Jan 1970 00:00:00 GMT
< Cache-Control: private, must-revalidate, max-age=0
< Last-Modified: Mon, 01 Feb 2016 19:43:50 GMT
< Location: http://rhel7/mediawiki/index.php/Main_Page
< Content-Length: 0
< Keep-Alive: timeout=5, max=100
< Connection: keep-alive
< Content-Type: text/html; charset=utf-8
< Proxy-Connection: keep-alive
* Connection #0 to host left intact


[root@rhel7 ~]# uname -a
Linux rhel7.example.com 3.10.0-327.4.5.el7.x86_64 #1 SMP Thu Jan 21 04:10:29 EST 2016 x86_64 x86_64 x86_64 GNU/Linux


[root@rhel7 ~]# grep -v "#" /etc/cntlm.conf 

Username    John.Smith
Domain      EXAMPLE.COM
Auth            NTLMv2
PassNTLMv2      121212121212121212112121212
Listen      3128

NoProxy     localhost, 127.0.0.*, 10.*, 192.168.*
  • 1
    Answer: I needed to add http_proxy and HTTPS_PROXY enviroment variables enable to use curl. Also – Jeight Feb 1 '16 at 20:26
  • Also, for anyone who is trying to use Docker through a proxy, you will need to edit /usr/lib/systemd/system/docker.service and add the following Environment="HTTP_PROXY=" "NO_PROXY=localhost," – Jeight Feb 1 '16 at 20:27
  • Did you need to set both http_proxy and HTTP_PROXY to get it to work? Did you try to figure out if you only needed to set one of them? That information might be useful to anyone who runs into the same problem. – gardenhead Feb 2 '16 at 0:14
  • 1
    I had to set both http_proxy and HTTPS_PROXY as global env variables, but only had to set HTTP_PROXY in the docker.service file. – Jeight Feb 2 '16 at 22:45
  • I had http_proxy set previously so yes I checked. I don't know if the applications check both lower and uppercase, but I know that I had to have https as well as http. – Jeight Feb 2 '16 at 22:49

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