1 2 Previous Next 27 Replies Latest reply: May 13, 2013 1:59 AM by Billy~Verreynne RSS

    IP problem

    HuaMin Chen
      Hi,
      I see eth0 is currently "192.168.168.20" that is the static IP I configured previously. How can I ensure the Oracle Linux machine is with the dynamic IP assigned by my ISP, as I am getting a problem to go to the Internet in this Oracle Linux machine.
        • 1. Re: IP problem
          HuaMin Chen
          The server is directly connected to outside, with the IP assigned by my ISP.
          • 2. Re: IP problem
            Billy~Verreynne
            HuaMin Chen wrote:
            The server is directly connected to outside, with the IP assigned by my ISP.
            Unlikely to be true, as a connection to an ISP would typically be via a modem or a router,

            You need to differentiate between your LAN and the Internet. The easiest is to configure DHCP on the router and use private addresses. E.g. 192.168.0.1 as the router address and 192.168.0.100 to 192.168.0.254 as the DHCP allocated block.

            You have then 2 choices.

            Use the router as a router - configuring the router to connect to the ISP and providing a route for all LAN devices on your home network, to the Internet. No special settings needed on any LAN device (which includes smartphones connecting via WiFi to your home router).

            Use the router as a bridge. Configure a PPPoE client on a LAN device (e.g. Windows 7 PC, or Linux PC). Initiate a PPPoE connection from the client, via the router, to the ISP.

            Both methods can be used at the same too - e.g. using the router as default Internet route, and having a specific LAN device do a PPPoE connection to a private network via the ISP.

            The default setup is using it as a router - and configuring the router as a DHCP server for the LAN and configuring it to make the ISP Internet connection.
            • 3. Re: IP problem
              HuaMin Chen
              Thanks a lot.
              Sorry, there is no router to the server as it is directly linked to ISP by the given cable.

              What to change in the server now, as normally it would be allocated with one IP addresss from the ISP?
              • 4. Re: IP problem
                Billy~Verreynne
                HuaMin Chen wrote:

                Sorry, there is no router to the server as it is directly linked to ISP by the given cable.
                How? What type of cable? 10baseT/100baseT? What wire protocol is supported by the ISP plug where the cable from the server plugs into the ISP?
                What to change in the server now, as normally it would be allocated with one IP addresss from the ISP?
                You need to explain in technical detail what technology this "connection to the ISP" is.
                • 5. Re: IP problem
                  HuaMin Chen
                  Do you understand I have a problem with eth1? By running ifconfig, why can't I see the IP of eth1?
                  • 6. Re: IP problem
                    Billy~Verreynne
                    What cable is plugged into eth1?

                    Into what is the other side of that cable plugged into?

                    And into what is eth0 plugged into?

                    There are more to assigning IP addresses than running ifconfig. Such as the actual network infrastructure the IP address would be running over. And that is what my question is - what is your network infrastructure? Just how do you plug an Ethernet cable from your server/PC/notebook into the ISP's network? Through what device?

                    Knowing the device, one can determine how to obtain an IP address and how to use this device to connect, via it, to the Internet.
                    • 7. Re: IP problem
                      HuaMin Chen
                      Very sorry for that, one thing has not been mentioned clearly.
                      This OL server is running within a Virtualbox. How to ensure eth0 and eth1 are fine?
                      • 8. Re: IP problem
                        AmitShil
                        Hi, below output would help debugging your situation.

                        1. what type of adapter is used in the Virtual box?
                        2. please give a ifconfig -a or "ip addr show" from the OEL VM
                        3. Also give the output of route -n from the OEL VM
                        4. Also give contents of the ifcfg-eth- and ifcfg-eth from the /etc/sysconfig/network-scripts directory

                        Regards Amit
                        • 9. Re: IP problem
                          HuaMin Chen
                          Sorry for I did have an issue to send out mails from this Vbox after I've captured these info you requested, as I did get internet access problem in it.
                          • 10. Re: IP problem
                            AmitShil
                            Hi, guess your reply means for some reason you are not able to post the output in here?

                            Are you not using a SSH client like Putty to access your VM? its very easy to copy paste content from putty over here

                            Regards Amit
                            • 11. Re: IP problem
                              AmitShil
                              Hi,

                              If you just want internet in your VM, then just select the NAT adapter in n/w settings of your VM, the DHCP server should assign a dynamic IP which would get NAT'ed to your host n/w and allow internet access in your VM.

                              Regards Amit
                              • 12. Re: IP problem
                                Catch~22
                                I suggest you familiarize yourself with the concepts of private networking.

                                For instance https://en.wikipedia.org/wiki/Private_network

                                If the IP you mentioned is assigned by your network provider it is already a private network. Private networks are not routed over the Internet and require NAT for outgoing and port forwarding for incoming connections. The VirtualBox NAT interface works the same way, albeit connecting to the network interface of your host computer.

                                To find out what your external or public IP address is, simply type "what is my ip" into the Google search field.
                                • 13. Re: IP problem
                                  EdStevens
                                  HuaMin Chen wrote:
                                  Very sorry for that, one thing has not been mentioned clearly.
                                  This OL server is running within a Virtualbox. How to ensure eth0 and eth1 are fine?
                                  Why didn't you mention that it was under VBox before? That is a very critical piece of information.

                                  Please read https://forums.virtualbox.org/viewtopic.php?f=35&t=42385
                                  • 14. Re: IP problem
                                    Catch~22
                                    I was wondering about your "n/w" abbreviation during your last couple of posts. I even searched in Google and the best I could find was north west, which did not make sense. So I guess it means "network"? ;-)
                                    1 2 Previous Next