Add instructions for use of HTTP_PROXY with systemd to docs (gravitat…

…ional#2752)

docs/2.0/admin-guide.md

@@ -974,6 +974,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/2.3/admin-guide.md

@@ -991,6 +991,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/2.4/admin-guide.md

@@ -1190,6 +1190,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/2.5/admin-guide.md

@@ -1339,6 +1339,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/2.7/admin-guide.md

@@ -1367,6 +1367,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/3.0/admin-guide.md

@@ -1479,6 +1479,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/3.1/admin-guide.md

@@ -1600,6 +1600,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/3.2/admin-guide.md

@@ -1586,6 +1586,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS

docs/4.0/admin-guide.md

@@ -1587,6 +1587,18 @@ The value of `HTTPS_PROXY` or `HTTP_PROXY` should be in the format
 `scheme://host:port` where scheme is either `https` or `http`. If the
 value is `host:port`, Teleport will prepend `http`.
 
+It's important to note that in order for Teleport to use HTTP CONNECT tunnelling, the `HTTP_PROXY` and `HTTPS_PROXY`
+environment variables must be set within Teleport's environment. You can also optionally set the `NO_PROXY` environment
+variable to avoid use of the proxy when accessing specified hosts/netmasks. When launching Teleport with systemd, this
+will probably involve adding some lines to your systemd unit file:
+
+```
+[Service]
+Environment="HTTP_PROXY=http://proxy.example.com:8080/"
+Environment="HTTPS_PROXY=http://proxy.example.com:8080/"
+Environment="NO_PROXY=localhost,127.0.0.1,192.168.0.0/16,172.16.0.0/12,10.0.0.0/8"
+```
+
 !!! tip "Note":
     `localhost` and `127.0.0.1` are invalid values for the proxy host. If for
     some reason your proxy runs locally, you'll need to provide some other DNS