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Pesky networking problem with Ubuntu / Debian

I'm running Ubuntu Server (Hardy) in our office. The building we are in provisions internet for us so we have fixed IP and DNS server. The problem is: I can't reach the internet from this server. It will resolve IP addresses but for example I can't apt-get or wget anything. Posted this problem on two other forums but no resolution yet. Would be open to any suggestions at this stage since everything I've tried doesn't work so far.

Code:

ifconfig -a:



eth0      Link encap:Ethernet  HWaddr 00:30:1b:46:b8:d8

          inet addr:193.168.1.200  Bcast:193.168.1.255  Mask:255.255.255.0

          inet6 addr: fe80::230:1bff:fe46:b8d8/64 Scope:Link

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:93 errors:0 dropped:0 overruns:0 frame:0

          TX packets:82 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:7360 (7.1 KB)  TX bytes:10754 (10.5 KB)

          Interrupt:17



lo        Link encap:Local Loopback

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:16436  Metric:1

          RX packets:6 errors:0 dropped:0 overruns:0 frame:0

          TX packets:6 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:0

          RX bytes:348 (348.0 B)  TX bytes:348 (348.0 B)

Code:

arp -a:



? (193.168.1.94) at 00:16:41:E7:A1:73 [ether] on eth0

SME100.SME (193.168.1.1) at 00:17:16:00:24:58 [ether] on eth0

Code:

interfaces:



# The loopback network interface

auto lo

iface lo inet loopback



# The primary network interface

auto eth0

iface eth0 inet static

        address 193.168.1.200

        netmask 255.255.255.0

        network 193.168.1.1

        broadcast 193.168.1.255

        gateway 193.168.1.1

        dns-nameservers 193.168.1.1 210.22.70.3 193.168.1.200

        dns-search com

Code:

resolv.conf:



search com

nameserver 193.168.1.1

nameserver 193.168.1.200

nameserver 210.22.70.3

Code:

I can resolve hosts:



XXX@XXX:/etc$ host google

google.com has address 64.233.187.99

google.com has address 72.14.207.99

google.com has address 64.233.167.99

google.com mail is handled by 10 smtp1.google.com.

google.com mail is handled by 10 smtp2.google.com.

google.com mail is handled by 10 smtp3.google.com.

google.com mail is handled by 10 smtp4.google.com.

Code:

But can't access internet:



PING google.com (64.233.187.99) 56(84) bytes of data.



[1]+  Stopped                ping google.com

Nothing happens, even after waiting 10 minutes

I cannot ping the DNS server

Code:

I can ping the gateway:

PING 193.168.1.1 (193.168.1.1) 56(84) bytes of data.

64 bytes from 193.168.1.1: icmp_seq=1 ttl=64 time=0.569 ms

64 bytes from 193.168.1.1: icmp_seq=2 ttl=64 time=0.412 ms

64 bytes from 193.168.1.1: icmp_seq=3 ttl=64 time=0.391 ms

64 bytes from 193.168.1.1: icmp_seq=4 ttl=64 time=0.376 ms

64 bytes from 193.168.1.1: icmp_seq=5 ttl=64 time=0.375 ms

64 bytes from 193.168.1.1: icmp_seq=6 ttl=64 time=0.370 ms

64 bytes from 193.168.1.1: icmp_seq=7 ttl=64 time=0.388 ms

Thanks in advance to anyone who has suggestions for how to fix this!

Show your router IP-related settings for the LAN.

Also, if your router is a cheap commodity router, don't use its internal DNS cache. They are very poor. Use your ISPs instead. (remove the 192.168.1.1 name server entry in resolv.conf, or wherever you configure your network settings).

Also describe the WAN side of your router - you can mask the IP if its public.

Wait a minute. I think you have a problem with your IP address and network

193.168.1.200

I think you want 192.168.1.200, which is a private network. 193 is public. Please confirm.

Unfortunately the router is managed by the building's IT department and I haven't been able to get much information from them yet, but I will try again today. I tried to determine the router's IP address from dyndns, but it couldn't resolve it, ping router also fails of course.

Before I only had the ISP's DNS server listed, but it wouldn't resolve hosts because I am not able to reach the DNS server, when I added 193.168.1.1 it can at least resolve hosts, though I am sure their router is cheap.

Seems like I am blocked at the gateway because I can ping it but not the DNS server or the router.

Unless you are in Europe and are part of the IP address range 193.0.0.0/8 :

Code:

$ whois 193.168.1.200



OrgName:    RIPE Network Coordination Centre

OrgID:      RIPE

Address:    P.O. Box 10096



...



NetRange:  193.0.0.0 - 193.255.255.255

CIDR:      193.0.0.0/8

NetName:    RIPE-CBLK

NetHandle:  NET-193-0-0-0-1

Parent:

...

% Information related to '193.168.1.0 - 193.168.1.255'



inetnum:      193.168.1.0 - 193.168.1.255

netname:      CU-CB-NET

descr:        Centre Universitaire

descr:        CU central building local network

descr:        Luxemburg

country:      LU

admin-c:      NS725-RIPE

i don't think you have the correct info.

Change your IP to 192 instead of 193. Watch what happens.

Quote:

Originally Posted by Mr. C. (Post 3209606)

Wait a minute. I think you have a problem with your IP address and network

193.168.1.200

I think you want 192.168.1.200, which is a private network. 193 is public. Please confirm.

Yeah I wondered about that too, but it is in fact 193! Odd thing is that with exactly the same settings (I tested the IP address), my win lappy is able to connect fine.

Quote:

Originally Posted by Mr. C. (Post 3209626)

Unless you are in Europe and are part of the IP address range 193.0.0.0/8 :

Code:

$ whois 193.168.1.200



OrgName:    RIPE Network Coordination Centre

OrgID:      RIPE

Address:    P.O. Box 10096



...



NetRange:  193.0.0.0 - 193.255.255.255

CIDR:      193.0.0.0/8

NetName:    RIPE-CBLK

NetHandle:  NET-193-0-0-0-1

Parent:

...

% Information related to '193.168.1.0 - 193.168.1.255'



inetnum:      193.168.1.0 - 193.168.1.255

netname:      CU-CB-NET

descr:        Centre Universitaire

descr:        CU central building local network

descr:        Luxemburg

country:      LU

admin-c:      NS725-RIPE

i don't think you have the correct info.

Change your IP to 192 instead of 193. Watch what happens.

I'm in Shanghai actually. The settings are correct, I verified that many times and as mentioned in the other post, they work on my windows machine (which I am using right now).

Luxemborg != China.

And this route isn't going to China:

Code:

8  DANTE.TenGigabitEthernet7-3.ar1.FRA4.gblx.net (207.138.144.46)  185.935 ms  176.342 ms  178.885 ms

9  so-1-3-0.rt1.lux.lu.geant2.net (62.40.112.54)  180.427 ms  176.461 ms  176.347 ms

10  restena-gw.rt1.lux.lu.geant2.net (62.40.124.150)  175.949 ms  181.449 ms  176.010 ms

11  gate-1.rest.restena.lu (158.64.16.62)  179.477 ms  180.510 ms  182.446 ms

12  gate-1-v25.limp.restena.lu (158.64.16.213)  182.662 ms  182.479 ms  181.936 ms

13  gate-1-v24.ucl.restena.lu (158.64.16.209)  180.886 ms  180.902 ms  182.408 ms

It might just be a remarkable coincidence.

Quote:

Originally Posted by Mr. C. (Post 3209605)

What information specifically should I ask them for re the router IP settings for lan and wan? If I'm not really specific they won't reply.

Well, the router is not cheap, so that's not a worry. According to your arp, it appears to be a fairly pricey SME-100 NatPass in the price range of about $1800-$2500 US :

SME100.SME (193.168.1.1) at 00:17:16:00:24:58 [ether] on eth0

MAC Address
Prefix Vendor
001716 Qno Technology Inc.

It can be difficult to work with IT folks I realize. If they gave you a static IP, you need to know :

IP
Netmask
Gateway (which will be their router)
Broadcast (you can infer this, but ask anyway)
DNS server IP(s) in order of priority

Further interest, your DNS servers:

193.168.1.1
210.22.70.3
193.168.1.200

The first one is your gateway (whose IP addr seems questionable)
The second one is... what do you know... in Shanghai
The third is your own linux box. Are you running a DNS server on this box? If so, use it as the primary DNS server. If not, remove it from the list of name servers.

Quote:

Originally Posted by Mr. C. (Post 3209682)

IP
Netmask
Gateway (which will be their router)
Broadcast (you can infer this, but ask anyway)
DNS server IP(s) in order of priority

When I started I asked them for the following information, their replies are in italics:
IP address: 193.168.1.200
Netmask: 255.255.255.0
Network ID: [no response]
Broadcast IP: [no response]
Gateway/Router IP: 193.168.1.1
DNS Server: 210.22.70.3 210.22.70.227

Unless they have a VPN connection to somewhere in Luxemburg, and your network is part of that VPN, they are hijacking public IP space that belongs to somebody else. Perhaps they have answers...

Deidgar,
Why not you yourself try this:
whois 193.168.x.x

You will yourself understand there is some problems with ip address. Or that you really do not have complete information about it.
If the ip range you are using are illegitimate, then you might just not get help here.
As Mr.C said, you need to find out if there is some VPN connection that you are connected to.

Noted, and I told the IT people here (they don't work for us, we're in a serviced office) that they should use the designated 192.168.x.x for private networks. Their response was "pffft".

Good news is the problem is now solved. Those lazy jokers hadn't updated their routing tables for the ip address they assigned. Waste of time! working fine now!