Set up Proxy using http_proxy, https_proxy and no_proxy in Linux

Behind a corporate or campus firewall, many Linux tools reach the internet only through an HTTP proxy. Exporting http_proxy, https_proxy, and no_proxy is the fastest way to make command-line programs — curl, wget, apt, git, and others — use that path without editing each tool separately.

This guide walks through temporary and permanent setup, lowercase vs uppercase variable names, authenticated URLs, no_proxy bypass lists, and per-tool configuration when environment variables are not enough.

What is a proxy server?

A proxy sits between your machine and the internet. Your client sends the request to the proxy; the proxy forwards it and returns the response. On Linux servers and desktops, HTTP proxies are the most common type you configure with environment variables.

Common proxy categories:

• HTTP proxies — web and API traffic over HTTP/HTTPS (most corporate setups).
• SOCKS proxies — broader traffic types (mail, FTP, some apps).
• SSL proxies — TLS between client and proxy endpoint.
• Transparent proxies — caching or policy enforcement; they do not hide your origin IP.

For browser-based workflows, some teams use third-party proxy providers or fingerprint-isolated browsers paired with managed proxy endpoints. That use case is different from configuring http_proxy on a Linux shell, but the same proxy concepts apply.

Quick reference

For most HTTP proxy servers, both http_proxy and https_proxy use an http:// URL. See the next section on lowercase vs uppercase names before you debug a tool that “ignores” your exports.

http_proxy vs HTTP_PROXY: lowercase or uppercase?

There is no single standard. Many programs read lowercase names, many read uppercase, and some read both — but not always with the same rules.

Practical guidance:

• Set lowercase http_proxy, https_proxy, and no_proxy first — they are the most widely documented.
• Also set uppercase HTTP_PROXY, HTTPS_PROXY, and NO_PROXY when a daemon or language runtime might only check uppercase (some Java, Node, and Python stacks do).
• curl is the important exception for HTTP: it uses lowercase http_proxy for http:// URLs and does not use HTTP_PROXY for HTTP because of historical CGI security concerns. It can use HTTPS_PROXY for HTTPS URLs.

On a clean shell, exporting only http_proxy sends HTTP requests through the proxy; exporting only HTTP_PROXY may let HTTP requests go direct while HTTPS still uses HTTPS_PROXY. Always verify with curl -v when behavior looks wrong.

Check what your current session has:

env | grep -i proxy | sort

Sample output:

http_proxy=http://proxy.example.com:8080
https_proxy=http://proxy.example.com:8080
no_proxy=localhost,127.0.0.1

Set http_proxy and https_proxy temporarily

Exports apply to the current shell and child processes. They are lost when you close the terminal unless you add them to a startup file (covered below).

Without username and password

For a typical corporate HTTP proxy, use http:// for both variables:

export http_proxy="http://proxy.example.com:8080"
export https_proxy="http://proxy.example.com:8080"

Example with a literal IP:

export http_proxy="http://192.168.1.1:8080"
export https_proxy="http://192.168.1.1:8080"

Use https://proxy.example.com:port in https_proxy only when the proxy service itself accepts HTTPS connections on that port. Most HTTP proxy appliances expect http:// even when the destination site uses HTTPS.

With username and password

export http_proxy="http://username:password@proxy.example.com:8080"
export https_proxy="http://username:password@proxy.example.com:8080"

With domain, username, and password

export http_proxy="http://mydomain\\user123:pass123@192.168.1.1:8080"
export https_proxy="http://mydomain\\user123:pass123@192.168.1.1:8080"

Verify the exports:

echo "$http_proxy"
echo "$https_proxy"

Special characters in proxy URLs

Usernames and passwords that contain @, #, $, &, or / must be URL-encoded or the shell and the URL parser will misread the string. See How to set up http or https proxy with special characters in username and password for a full walkthrough.

Common encodings:

Example — password $&@pass becomes %24%26%40pass:

export http_proxy="http://user123:%24%26%40pass@192.168.1.1:8080"
export https_proxy="http://user123:%24%26%40pass@192.168.1.1:8080"

Credentials in environment variables are visible to other processes on the same host (/proc/PID/environ). Prefer tool-specific credential files when your security policy requires it.

Set proxy environment variables permanently

Temporary export lines disappear after reboot. For persistence, use user-level shell startup files or system-wide files. More background on load order is in where to set environment variables in Linux.

Per user (~/.bashrc or ~/.profile)

vi ~/.bashrc

Add at the end:

export http_proxy="http://username:password@proxy.example.com:8080"
export https_proxy="http://username:password@proxy.example.com:8080"
export no_proxy="localhost,127.0.0.1,.example.com"

Apply immediately:

source ~/.bashrc

On zsh, use ~/.zshrc instead. On fish: set -gx http_proxy 'http://proxy.example.com:8080'.

System-wide (/etc/environment)

/etc/environment is not a shell script — do not use export.

sudo vi /etc/environment

Add:

http_proxy="http://username:password@proxy.example.com:8080"
https_proxy="http://username:password@proxy.example.com:8080"
no_proxy="localhost,127.0.0.1,.example.com"

Log out and back in (or reboot) for login sessions to pick up changes.

System-wide login shells (/etc/profile.d/)

For scripts that run at login on many distributions:

sudo tee /etc/profile.d/proxy.sh <<'EOF'
export http_proxy="http://proxy.example.com:8080"
export https_proxy="http://proxy.example.com:8080"
export no_proxy="localhost,127.0.0.1,.example.com"
EOF
sudo chmod 644 /etc/profile.d/proxy.sh

Bypass the proxy with no_proxy

no_proxy (and NO_PROXY) lists hosts that should connect directly. Values are usually comma-separated.

Local and loopback:

export no_proxy="localhost,127.0.0.1,::1"

Internal DNS suffixes:

export no_proxy="localhost,127.0.0.1,.example.com"

Private RFC1918 ranges (common in labs):

export no_proxy="10.0.0.0/8,192.168.0.0/16,172.16.0.0/12"

Wildcards and mixed lists:

export no_proxy="*.example.com,.example.org,127.0.0.0/8"

Persist no_proxy in the same files as http_proxy (~/.bashrc, /etc/environment, or /etc/profile.d/proxy.sh).

Verify:

echo "$no_proxy"

Use curl and wget with a proxy

curl

Without authentication:

curl -x http://proxy.example.com:8080 http://example.com

With authentication:

curl -U username:password -x http://proxy.example.com:8080 http://example.com

When environment variables are set, curl picks up lowercase http_proxy / https_proxy automatically. Force a direct connection to localhost when a proxy is exported:

curl --noproxy '*' http://127.0.0.1:8080/

Use curl -v to see whether traffic goes through proxy.example.com or direct.

wget

One-off proxy on the command line:

wget -e use_proxy=yes -e http_proxy=http://proxy.example.com:8080 http://example.com

With credentials in the URL:

wget -e use_proxy=yes -e http_proxy=http://user:pass@proxy.example.com:8080 http://example.com

When http_proxy and https_proxy are exported, a plain wget http://example.com uses them. wget also reads ~/.wgetrc and /etc/wgetrc — if exports seem ignored, check for overrides there. See the GNU wget proxy manual.

Configure proxy for apt and apt-get

sudo apt update does not always inherit your user shell exports. Configure APT directly:

sudo tee /etc/apt/apt.conf.d/95proxy <<'EOF'
Acquire::http::Proxy "http://proxy.example.com:8080/";
Acquire::https::Proxy "http://proxy.example.com:8080/";
EOF

Authenticated proxy in the URL:

Acquire::http::Proxy "http://user:pass@proxy.example.com:8080/";
Acquire::https::Proxy "http://user:pass@proxy.example.com:8080/";

If the proxy requires authentication and you do not want credentials inside /etc/apt/apt.conf.d/95proxy, use APT authentication configuration such as /etc/apt/auth.conf or /etc/apt/auth.conf.d/ where supported by your APT version and distribution. See Debian APT proxy configuration.

Test:

sudo apt update

Remove the file when you no longer need a proxy: sudo rm /etc/apt/apt.conf.d/95proxy.

dnf and yum (RHEL, Rocky Linux, AlmaLinux)

Add to /etc/dnf/dnf.conf:

proxy=http://proxy.example.com:8080
proxy_username=user
proxy_password=pass

Then run sudo dnf makecache or sudo dnf update to test.

Configure proxy for Git

Git reads http.proxy and https.proxy from configuration — independent of shell exports unless you rely on environment variables.

Set globally:

git config --global http.proxy http://proxy.example.com:8080
git config --global https.proxy http://proxy.example.com:8080

Unset:

git config --global --unset http.proxy
git config --global --unset https.proxy

Verify:

git config --global --get http.proxy

Configure proxy for Docker containers and builds

Environment variables in your shell do not configure the Docker daemon. For client operations (pull, build), Docker reads ~/.docker/config.json:

{
  "proxies": {
    "default": {
      "httpProxy": "http://proxy.example.com:8080",
      "httpsProxy": "http://proxy.example.com:8080",
      "noProxy": "localhost,127.0.0.1,.example.com"
    }
  }
}

Create or merge that block into ~/.docker/config.json. New builds and containers started by the CLI can inherit these values.

Proxy with npm and pip

Node and Python tools often honor uppercase proxy variables:

export HTTP_PROXY="http://proxy.example.com:8080"
export HTTPS_PROXY="http://proxy.example.com:8080"
export NO_PROXY="localhost,127.0.0.1"
npm install express

For pip:

pip install --proxy http://user:pass@proxy.example.com:8080 somepackage

Or export http_proxy / https_proxy before pip install in the same shell.

Why proxy works as a normal user but not with sudo

sudo resets most environment variables unless your administrator allows them through.

Preserve your environment for one command:

sudo -E apt update

Or pass variables explicitly:

sudo env http_proxy="$http_proxy" https_proxy="$https_proxy" no_proxy="$no_proxy" apt update

For permanent sudo access, a sysadmin can add to /etc/sudoers via visudo:

Defaults env_keep += "http_proxy https_proxy no_proxy HTTP_PROXY HTTPS_PROXY NO_PROXY"

Systemd services never read your ~/.bashrc. Add Environment=http_proxy=... in a service drop-in under /etc/systemd/system/your.service.d/ when a daemon needs a proxy.

Unset or remove proxy environment variables

To remove proxy settings from the current shell:

unset http_proxy https_proxy ftp_proxy all_proxy no_proxy
unset HTTP_PROXY HTTPS_PROXY FTP_PROXY ALL_PROXY NO_PROXY

Verify:

env | grep -i proxy

If you configured proxy permanently, also remove the entries from ~/.bashrc, ~/.profile, /etc/environment, /etc/profile.d/proxy.sh, or the tool-specific configuration file.

Troubleshooting http_proxy and https_proxy issues

Summary

You can point Linux CLI tools at an HTTP proxy by exporting http_proxy, https_proxy, and no_proxy, using http:// URLs for both HTTP and HTTPS in most corporate setups, and mirroring lowercase names with uppercase when needed. Persist values in ~/.bashrc, /etc/environment, or /etc/profile.d/. Tools such as apt, Git, and Docker often need their own configuration or sudo -E — shell exports alone are not always enough.

References

• IBM — environment variables in Unix
• curl manual — environment variables
• GNU wget — proxies
• RFC 3986 — URI encoding
• Debian wiki — APT proxy configuration
• Docker — configure proxy for the CLI
• Git — git config documentation