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I'm into a little dilemma here. I bought a server, running Ubuntu, having 255 IP addresses and now I need to see them. I've searched the internet before posting here and found out that the command "ip address show" would spit up all my IPs, but instead it shows me this :

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet scope host lo
inet6 ::1/128 scope host
   valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:11:09:3b:3c:62 brd ff:ff:ff:ff:ff:ff
    inet x3.xx5.x4.10/27 brd x3.xx5.x4.255 scope global eth0
    inet6 fex0::2x1:xff:fxb:3cx2/64 scope link
       valid_lft forever preferred_lft forever

Do I really have those IPs ? Is this the right command ? Maybe I don't know how to read.

Later edit for ErikA:

sudo ifconfig shows:

eth0      Link encap:Ethernet  HWaddr 00:11:09:3b:3c:62
          inet addr:x3.xx5.xx4.10  Bcast:x3.xx5.xx4.255  Mask:
          inet6 addr: xx80::2x1:xff:fx3b:xc62/64 Scope:Link
          RX packets:2722000 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2673250 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1477640288 (1.4 GB)  TX bytes:319971949 (319.9 MB)

lo        Link encap:Local Loopback
          inet addr:  Mask:
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:918033 errors:0 dropped:0 overruns:0 frame:0
          TX packets:918033 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:99535482 (99.5 MB)  TX bytes:99535482 (99.5 MB)

It's not a hosting company, I get the IPs from the ISP. I just need to know what are my IP addresses, for paying the bill, not to get pwnd at pricing.

Maybe the server is not configured ? Can you please give me some keywords that i should look into over google ? Some guides, infos, anything. I really need to do this configuration.

share|improve this question
Pool of addresses assigned to you by ISP and pool of addresses configured on the server don't have to be the same. On the server you can use for example only one of them (or more...). – 0xFF May 2 '13 at 5:36
up vote 2 down vote accepted

How you do you know you have 255 IP addresses? Were you given a /24 subnet with the server? While this is technically possible, it's highly unlikely that any colo or hosting company would agree to provision that many IPs to a host (unless you were given an IPv6 allocation, which I guess could be possible, though unlikely).

You'll need to ask your host what subnet is available to you. Once you have that information, you'll need to set up subints (eth0:0, eth0:1, etc.) for each IP address. To do that, edit your /etc/network/interfaces file and add a group of lines like this for each assigned IP address, of course incrementing the number following the ":" for each group.

auto eth0:0
iface eth0:0 inet static

auto eth0:1
iface eth0:1 inet static

auto eth0:2
iface eth0:2 inet static


Restart networking when that's complete and all of your IP addresses should be available to you.

--Edit-- As mentioned above, you're going to need to get your IP allocation information from your ISP. Unless your server came pre-configured with the IP address information, there's really no way to tell what IP addresses are yours to play with. I can see that eth0 is currently configured with a /27 netmask, which contains 30 IP addresses (28 usable, after taking away the default route and broadcast), so that's not your main allocation. You're just going to need to talk with your ISP - that's the only way you're going to resolve this.

share|improve this answer
@pax - see the edit I made to the above answer. – EEAA Aug 27 '10 at 4:52
the content of /etc/network/intefaces: auto eth0 iface eth0 inet static address x3.xx5.xx4.10 netmask network x3.xx5.xx4.0 broadcast x3.xx5.xx4.255 gateway x3.xx5.xx4.1 – pax Aug 27 '10 at 4:53
Thanks for the info, pax, bit unfortunately the contents of that file means nothing as far as what ip addresses are allocated to you. – EEAA Aug 27 '10 at 5:04

To show your server's ip address, run "sudo ifconfig".

Your screen capture shows your loopback which is and your eth0 which is your network card, to me it doesn't seem to be configured.

It would be helpful if you could tell us what you are trying to achive.

share|improve this answer
ifconfig does not need to be run by root. On most systems, any user can execute it via $ /sbin/ifconfig. – EEAA Aug 27 '10 at 4:43
please check back on me, i did a "later edit" on my initial post. – pax Aug 27 '10 at 4:45
@pax - the above answer was made by CChock, not by me. I just edited it to clean up some grammar/formatting issues. – EEAA Aug 27 '10 at 4:52

The server doesn't know which IPs point to it, it only knows which ones it has been configured to listen on. Likewise, you can configure IP addresses on the server that don't resolve to it (don't do this) so ifconfig is no indication of the actual allocation.
The first step is to find out which IP addresses you have (if you're paying for them, ask for them), the second step is to set them up.

share|improve this answer

If you've been allocated IP's by your ISP they will know the range and should be able to advise.

From what you've said though I think you're trying to figure out how many IP addresses you are using so you can get rid of those you aren't using. If that's the case then the answer is you are using 1 IP Address on that server. You most likely are using more than that though, at least one in your assigned range from your ISP will be your routers IP Address.

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