CentOS 7 - Proxy Server

Alex Sage

In CentOS 7, what command(s) do I run to tell it to use a proxy server to connect to the internet?

scottalanmiller

the basic setting is...

http_proxy=http://proxy_server_address:port

scottalanmiller

You can run that while your shell is running. To set it for a user, it is typical to put it into their ~/.bash_profile file. Or put it into /etc/profiles to apply to all users. Be sure to export it as well.

Alex Sage

@scottalanmiller will that work even after reboot?

scottalanmiller

@anonymous said:

@scottalanmiller will that work even after reboot?

Not if you don't put it into one of the files mentioned

Alex Sage

Loaded plugins: fastestmirror
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock error was
14: curl#7 - "Failed to connect to 2a02:2498:1:3d:5054:ff:fed3:e91a: Network is unreachable"


 One of the configured repositories failed (Unknown),
 and yum doesn't have enough cached data to continue. At this point the only
 safe thing yum can do is fail. There are a few ways to work "fix" this:

 1. Contact the upstream for the repository and get them to fix the problem.

 2. Reconfigure the baseurl/etc. for the repository, to point to a working
    upstream. This is most often useful if you are using a newer
    distribution release than is supported by the repository (and the
    packages for the previous distribution release still work).

 3. Disable the repository, so yum won't use it by default. Yum will then
    just ignore the repository until you permanently enable it again or use
    --enablerepo for temporary usage:

        yum-config-manager --disable <repoid>

 4. Configure the failing repository to be skipped, if it is unavailable.
    Note that yum will try to contact the repo. when it runs most commands,
    so will have to try and fail each time (and thus. yum will be be much
    slower). If it is a very temporary problem though, this is often a nice
    compromise:

        yum-config-manager --save --setopt=<repoid>.skip_if_unavailable=true

Cannot find a valid baseurl for repo: base/7/x86_64

Maybe it's a IPV6 issue? Maybe the proxy hates me?

Alex Sage

Ping doesn't work ether

Alex Sage

I can ping the proxy, so no issue there.....

scottalanmiller

@anonymous said:

Ping doesn't work ether

Ping doesn't work in what way? You said that you can ping the proxy, so it sounds like ping it working.

Alex Sage

@scottalanmiller I just tried to ping google.com

scottalanmiller

You are on IPv6? You have an IPv6 connection from your ISP?

scottalanmiller

@anonymous said:

@scottalanmiller I just tried to ping google.com

But I thought that you put in an HTTP Proxy?

Alex Sage

@scottalanmiller I did.

scottalanmiller

@anonymous said:

@scottalanmiller I did.

Then how would you ping it? Are you trying to ping it FROM the proxy?

Alex Sage

@scottalanmiller said:

You are on IPv6? You have an IPv6 connection from your ISP?

No. But isn't this a IPV6 address?

"Failed to connect to 2a02:2498:1:3d:5054:ff:fed3:e91a: Network is unreachable"

scottalanmiller

@anonymous said:

@scottalanmiller said:

You are on IPv6? You have an IPv6 connection from your ISP?

No. But isn't this a IPV6 address?

"Failed to connect to 2a02:2498:1:3d:5054:ff:fed3:e91a: Network is unreachable"

Yes, so you have IPv6 being used somewhere. You need to get everything onto IPv4 if you want that to work

scottalanmiller

Since that address would have to have come from DNS, I assume, then maybe the proxy things it is on IPv6 and is requesting AAAA records.

Alex Sage

I am assuming when the proxy is working correctly I will be able to ping google.com from this server.

scottalanmiller

@anonymous said:

I am assuming when the proxy is working correctly I will be able to ping google.com from this server.

No, the purpose of using a web proxy is to block that, not allow it. You have no path for the ping to get to google.com since you just put in a proxy to block that.

scottalanmiller

If you accidentally forgot to lock down your firewall and left the routes on your server, then ping would continue to work as before, but then a proxy would be pretty silly as it wouldn't be doing its job in most cases. Assuming you configured the firewall to block outbound traffic that doesn't come from the proxy server, there would be no route for a ICMP packet to take to get to the Internet since the server isn't on the Internet anymore.