Ubuntu Networking :: Ping To Offline Host Returns Arbitrary Ip Address?
Mar 17, 2011
A brief description of my network:It is a small home network consisting of an Ubuntu 10.04LTS server edition, an Iomega ix2 NAS, a WinXP pro server and several family laptops.This is all routed through a Netgear WNDR3300 home router. All are assigned IP's via DHCP and all but the laptops are static (via DHCP though). The WAN address/DNS is assigned via DHCP from my ISP.The problem:When one of the machines is offline, Ubuntu does not resolve the netbios name correctly. No surprise here. But what is happening is that it is finding some arbitrary machine on another network. Below is what a ping to an offline host reveals:
Is it possible to forward a connection to a port to a completely unrelated external address? For example, I want to redirect ssh traffic to a.b.c.d to w.x.y.z. If w.x.y.z were an internal address and the machine was the router, this would just be plain old NAT port forwarding. But what if w.x.y.z is not an internal address? The reason I want to do this is I want to reassign a domain name example.com from ip address A to B, while allowing users to still ssh into A by using the [URL] domain name. Is this unreasonable? (I am guessing it is unreasonable, since the A wouldn't have it's gateway set to B, as is the case if A were in B's NAT'd internal network.)
I am using an virtual machine. where I need to ping from one machine to another. earlier I was able to ping. But after going to google.com once, I cannot ping back to this machine.
But if I gave ping -I eth1 <IP> then I can ping.
I cannot install any package, so tell me solution which includes not installing any package.
Code:$ host 80.159.xx.xxxHost 222.79.xxx.xxx.in-addr.arpa not found: 3(NXDOMAIN)What does this mean? The person currently using the IP address in IRC is chatting right now, but how come if he's online it doesn't return any information?
I am using ubuntu 9.10 and I still cannot figure out this thing. I work behind a proxy managed by my university. Now, I cannot ping the other users on my network although they can ping me. Not to mention, I also cannot ping [URL]... It says : ping: unknown host [URL]... But I can ping the proxy server.
I have a somewhat complicated network setup that I am testing on an internal network. I have the following route setup:
PC Client (192.168.2.100) --> Router (192.168.2.1) --> DSLAM (on our internal network) --> PPPOE Server (192.168.9.1) on Linux Ubuntu 8.04 on interface card eth2.
On the same Linux Ubuntu Machine on interface card eth1 (static IP 192.168.5.100), I have an Asterisk SIP server plugged into it. SIP Server = 192.168.5.101 (static) I need the PC client (192.168.2.100) to register via SIP soft phone to register on the SIP server (192.168.5.101). From the PC client I can ping as far as the eth1 interface (192.168.5.100)...but cannot ping the SIP Server (.101).
From the SIP server (192.156.5.101)...I can ping 192.168.5.100, I can ping 169.254.5.228 (Eth2:avahi), but not sure what that is. I cannot ping the pppoe default gateway (192.168.9.1), which I think you cannot anyway. No firewalls are running. My IPtables I cleaned out totally. I think it might be as simple as a route add, but I really have no clue. Tried building a virtual bridge using brctl LINUX betweeh eth1 and eth2, but that made things worse (could not ping anything after that)
If I try ping a host on my internal lan from my ubuntu notebook the host name never resolves, but if I ping www.domainname.xxx it will resolve because our dhcp server is setup as the dns server too. If I use the connect to server tool and select samba share and specify host by name, it can resolve that and the shares show up... same dns server, same machine, but different interface/program. My real reason behind this is because my synergy+ keeps falling over whenever the synergy servers dhcp lease expires and it gets a new I have to then specify the new address and change configs.
I made an ip packet using raw sockets and used icmp header of echo request inside that ip packet.I have a wifi lan with 2 host(laptops) connected to it. when I send the packets to any of these host the reply me with echo reply as i see in wireshark. but when i change the source ip and mac to that of another host there is no echo reply packet in the network but only echo request packet is there. Can anybody tell me why is this happening. and am also using Promiscuous mode so non of the packet is discarding.
I have a server that I can ping, and I can connect remotely with ssh to it. But when I try to connect to apache (port 80) I get "no route to host". But I can connect to localhost It's not just my client system that is having this problem but also systems that are on the same subnet There is no firewall running on the server route on the server
my network expertise is tenuous at best. This started because one computer on my network is having trouble updating Google Toolbar information. This is a laptop which joins other wifi networks outside of the house.
I have installed openvpn on an ubuntu 10.04 server. I run 11.04 on my desktop. It can connect to my VPN server. The problem is, I have ZERO internet access. I cannot even ping an IP address.
I am working behind a http proxy (172.30.x.x:3128). I have configured it in my terminal. All the applications such as wget,lynx firefox etc. are working correctly.However all dns utilities like nslookup, host and even ping too are not working.Following is output of host command:
Code: root@ding:~# host google.com ;; connection timed out; no servers could be reached Output of host -T:
[Code]....
To connect to net I have to first run dhclient3(learnt from this forum!).It gives me my ip but where is dns address sent I don't have and idea.
I've encountered a problem after doing a fresh install with xubuntu 10.10 (2.6.35-23-generic).some sites are blocked like [url]....if I do dig [url]....- I receive the A, CNAME records and the IP address and everything.when ping[url].... - I receive 'unknown host'.when ping <theipaddress> - I receive responses
Something strange with my firewall i used firestarter I dont know why i cannot ping outside on a specific IP address here is my setup. I have IP from ISP
119.92.56.77 - eth0 192.168.50.1 - eth1
with DHCP features from 192.168.50.1 - 254. my problem is i cannot ping this specific IP address which is 119.93.232.234 if you can try there and pinging is ok but here cannot because that IP address (119.93.232.234) they used that to connect to our openvpn which is the IP is 119.92.56.78 <---- this system linux(centos) or IP has no firewall enabled. meaning i separeted this connection. which my setup is like this for OPenVPN
Since two days i m not able to browse websites using the domain names but able to ping/browse using IP addressed. I have done the following:
1. Using wireless i m able to get IP address of DNS (8.8.8., Gateway, localhost & router ip address 2. Disabled wireless and connected ETH0 but still the same problem 3. not able to edit resolv.conf
sudo gedit resolv.conf ** (gedit:4179): WARNING **: Hit unhandled case 0 (Error opening file: Input/output error) in parse_error.
I had configured Squid in RHEL 5 and facing an issue with pinging. Not able to ping any website,hostname is resolving to ip address but not able to ping
I have a server with centos 5 and plesk 9 and I have buy an additional IP address for my server, when i create it in plesk, there is no problem, all its ok I can assign it to a new domain, but the ip only responds ping, none of other services as http, ssh or smtp.I paste here the configuration of files
I can ping a host on my LAN successfully, but I cannot ping [URL]... for example. I have disabled the firewall and set http_proxy and can browse the internet with "Use system proxy settings" checked in Firefox. I am unable to update with yum either, but I am not sure if this is a side effect or not. I have run a trace on my ip address as I am browsing the internet and I can see the sites I am visiting on our web appliance. However, if I try to ping or update no requests are hitting the proxy so I don't think that is the issue.
I have a machine running linux with 3 ethernet interfaces attached.
My Ifconfig:
My route output:
eth0 is attached to a laptop, eth1 is attached to a PC. eth2 is attached to a DSL modem, and the server is successfully acting as my internet gateway. The trouble is, my PC cannot see my laptop and vice versa. E.G. cannot ping, host seems down.
This is a RHEL 5.4 install. I did a fairly routine install setting up a static IP address of 10.5.96.10, a subnet mask of 255.255.254.0, and a gateway of 10.5.96.1 with the standard DNS setup for this network. These are all standard network setting for this network and otherwise work fine on other systems. The IP, gateway, and subnetmask all appear correctly on all relevant configuration files. This server can not ping any other system on the network and can not ping its default gateway. No other systems can ping this one either. Also this system can not ping "localhost" or its own hostname. The hosts file contains the line:
[code]...
I can ping 127.0.0.1 and 10.5.96.10 and it works fine. Also the firewall is disabled. I know I probably can't get a straight forward fix with the information I have on hand right now, I'm more of a Debian guy, so there might be some Red Hat intricacies I'm not familiar with. I think I had a CentOS install some months back that had this issue and I don't remember how I fixed it, or if I even did. I might have just replaced it with Debian. That's unfortunately not an option this time around since it's not my box.
I run an centos server. From the console I can ping google.com and get a reply. But when I ping another address say xyz.com, the IP address is resolved (11.22.33.44) but there is no reply. In the same network in our office from my desktop I ping [URL] and there is a reply.I turned of the firewall but still the same problem.
I am setting up a server, with a static IP address. I thought I did the setup correctly, including setting up the static IP address. When the system restarted, I saw a message flash about some other host already uses address 72.86.26.xxx
Then, once logged in, I got a system message: System is not receiving updates, check network connection.
I went to System: Network Configuration, and under Devices, I saw:
Inactive Device: eth0
I clicked on activate, and I received the same message: some other host already uses address 72.86.26.xxx
The file /etc/sysconfig/networking/devices/ifcfg-eth0 reads:
I've only been using linux for a few days so I don't know all the tricks. I'm pretty savy configuring windows networks however.My adapter is (according to windows) a: CNet PRO200WL PCI fast ethernet adapterLinux says it is a: 21x4x DEC-tulip compatible 10/100 EthernetI do seem to be getting an ip address from the DHCP router, but I cannout ping any other ips or connect to the internet.I've tried a bunch of different options, switching things back and forth, but it still doesn't work, and honestly i don't even know what some of the options mean.
ALSO, if this helps: paladin:~ # ifconfig eth0 Eth0 Link encap:Ethernet HWaddr 00:08:A1:03:3C:99
