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I've set up a VM running Debian Squeeze within VMware ESXi 5.0. It has a running webserver and some other stuff. My goal is to access this machine by its hostname from other computers in my local network. This isn't working, currently I can only access this VM with its IP address.
In my network is a Windows Server 2003 running (as a domain controller with an AD), which is also a DHCP server.
My VM correctly gets an IP address from the subnet 192.168.115.0/24. It can also ping and access other machines from the network by their name after I installed winbind. But the other way around doesn't work, other machines can't find the hostname of this VM.
I have captured the process when my Win7 machine tries to ping this VM by its hostname. Wireshark shows me the following (.100 is the server, .103 is my local machine):
43 2.700104 192.168.115.103 192.168.115.100 NBNS 92 Name query NB INFORMATIX2<00>
44 2.700487 192.168.115.100 192.168.115.103 NBNS 98 Name query response, Requested name does not exist
45 2.720377 192.168.115.103 192.168.115.255 NBNS 92 Name query NB INFORMATIX2<00>
So I guess my server doesn't know the VM, despite having delivered an IP address to it.
What is wrong here?
Ok, I found the problem. The cause was that my Linux machine hasn't enabled dynamic DNS updates (see also manpage of dhclient.conf, section 'DYNAMIC DNS'). This thread had the right hint for me - I have to edit my dhclient.conf and add send host-name "debian-vm"; to it. Despite what is written at the manpage, the hostname is sufficient - I don't need the fqdn.
Now it works - I can access my VM from every other machine in my network. To verify this, I looked at DHCP server settings from the Win2k3 server and checked the leases. Now the name of my VM is shown in the column 'name' - it was empty before the change.
I have to add another piece of information: If you setup the DHCP server of Win2k3 to deliver a specific IP to the MAC address of your VM, it is necessary to activate "updates of DNS-A and -PTR entries for clients which do not request updates" in the properties of your DNS reservation.
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We are provided with LAN inside our hostel, ip address starts from 172.... But few of days ago we start getting ip address of something like 192.... and internet stops working. We are told to fill static ip in setting( by seniors) in order to use internet. We did it ,internet starts working but i don't know why after that i am not able to ping anything like
wheneer i type ping 8.8.8.8 it goes into loop, there is a server inside our college with address glug.nith.ac.in whenever i try to ping that with the given name like ping glug.nith.ac.in it says
ping: glug.nith.ac.in: Name or service not known
whenever i try to ping that server with its ip address like 172...__ it again goes into loop.
SSH too not working.
Why so ? And what's going arround with network in layman term?
ping: glug.nith.ac.in: Name or service not known
is because your DNS Server is not reachable from your system. So the website you are accessing cannot be mapped into an IP address. IP address helps you to make calls to the website servers and load the response contents. Since its not reachable, you are getting Name or service not known error.
192...
This always is the local network IP address assigned to you when you are connected to a WIFI Router or other routers in LAN(Local Area Network). If these routers doesn't have any incoming internet connections, then they create their own subnet and your system will be a part of this subnet. You wont have access to the internet in most of the cases.
172...
Now this could be your IP address allowed to access the internet according to DHCP server (the server that maintains the IP address allocations and Internet accesses). Hence you are able to access the Internet.
I tried my best to keep it simple though there are lot many concepts involved here. I would recommend you to go through Data communications and networking by Behrouz A. Forouzanif are interested to know more. Hope this helps. :)
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I'm trying to set up a group of VM's using MAAS with vagrant and virtualbox using a host only network shared between the VMs. I'm trying to get the node VMs to use PXE to install the operating system. I've got the node VMs to start PXE booting by setting up DHCP on the controller VM and forcing the node VM to boot from the second nic. The installation gets part of the way through before stopping when cloud-init tries to download the config. My Vagrant file is at https://gist.github.com/pj/3db0fe2e87cf35d4f6ffb37a5b5b8bb6.
As far as I can tell, MAAS is delivering the address to cloud-init through the cloud-config-url boot parameter. From looking at the output when the PXE node tries to boot I can see that the address being delivered contains the ip address of the NAT nic that Vagrant automatically creates for VMs, not the ip address of the host-only network which was used for DHCP and to deliver the PXE boot files.
Is there a way to change the ip of the cloud-config-url boot parameter? In the MAAS source it seems like this is derived from some part of the RackController config, but I couldn't trace where it was set from.
Okay figured it out, I needed to set the url for the rack and region controller using the following commands:
sudo maas-region local_config_set --maas-url="http://192.168.50.2:5240/MAAS"
sudo maas-rack config --region-url="http://192.168.50.2:5240/MAAS"
In our setup, instead of forcing slave nodes (the one that PXE-booted and managed by MAAS controler) to use host-network IP as shown above, we have made the MAAS controller a router for its managing subnet. This is a more robust configuration and closer to an actual environment.
From what we have seen, these nodes, once PXE-booted, need internet access in order to load more packages on top of OS. Otherwise, they can be in an intermediate state and never finish "deploy" until a timeout error.
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I'm trying to connect Winscp with virtual machine. I'm working on Windows,and this problem is killing me for 5 hours. Studied a lot of examples, but I can't find out what is the problem. I tried to connect with putty to, but connection is every time refused. Tried to connect with every protocol, but didn't help. I even can't install ssh into Ubuntu, because something is blocking but not firewall(failed to fetch us archive ubuntu com). Port forwarding too wasn't very helpful.
1st Adapter is NAT, and second host-only.
Problem is that I need to enter home directory, and add some files, so I'm trying to find the easiest way to do this.
I would really appreciate any help. Here is my ifconfig, ip a, and interfaces picture.
1
Thanks!
Use the following step to configure.
1- Run ipconfig /all on your windows machine and see which ip are assigned to your virtual adopters.
2- Assign the same range ip to your virtual machine. For example:
If on virtual adopter ip is: 192.168.130.1
Then assign ip to your vm as: 192.168.130.*
and set gateway to : 192.168.130.1
and restart the service network and check the reachability by pinging from both side.
3- If You able to ping then you will be able to use internate on your VM. Then install the ssh.
Now you will be able to use.
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First of all, I'm beginner at this, so don't be too harsh.
Yesterday, I wanted to make Linux Server. Installed LAMP, PhpMyAdmin. Man the websites IP static. I installed moodle on my website server. Then I closed VirtualBox and went to sleep.
Today when I runned my server and tried to access /phpmyadmin or (ipaddress)/moodle it says that webpage isn't available. Does this mean I have to do everything from the scratch again?
I'd appreciate any help.
I tried command sudo service apache2 start , but nothing changes.
Run this command in Terminal:
sudo service apache2 restart
OR
sudo restart apache2
Try the Answer on this Post
There are a lot of basic troubleshooting steps to take here.
You mentioned "localhost" in your question, but this doesn't sound like the local host; if you're connecting to your guest machine from the host machine then both machines will treat it as a networking connection (because it is networking). How that networking is configured will depend on your VirtualBox configuration.
Are you sure the virtual machine is running, the IP address is assigned, and networking is, well, working? Try pinging the virtual/guest machine from the host machine. After pausing and resuming, one of my Debian machines used to always pick up a DHCP address on the host-networking adapter despite being set to a static address in /etc/network/interfaces. Look at ifconfig to verify the IP address listed is what you expect.
Are you sure Apache is running? Try accessing it from within the guest machine on http://localhost -- by telnet to port 80, command-line tool, or full-on web browser.
Are other services working? Try to connect remotely to whatever you have running: SSH, FTP, IMAP, MySQL, NTP -- try to connect and see if the problem is the network or the service.
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All firewalls are turned off.
I have 3 Fedora 20 machines and 1 Windows 7 machine on the same 172.x.x.x LAN.
They all have static IP addresses and same subnet. (255.255.255.0)
The Fedora machines can all ping each other.
The Windows 7 machine can ping all 3 Fedora machines.
The Fedora machines, however, cannot ping the Windows 7 machine. I get the response: Destination Host Unreachable.
I ran Wireshark on the Windows machine. ICMP messages show up when pinging from Windows to Fedora, but not the other way around.
To further complicate matters, all machines also have a second network adapter hooked up to a second 10.x.x.x network. On THIS network, all machines CAN ping each other, Windows to Fedora AND Fedora to Windows. It's just the 172.x network where the Fedora machines cannot ping the Windows machine.
I know
there are tons of posts out there already for "cannot ping" issues,
but I haven't been able to find anything that helps with this
specific scenario. Or when I do, it turns out to have been a firewall
issue, and there is no firewall running on these machines.
Any thoughts?
Thank you.
On the Windows machines, make sure that the Network Discovery protocol is turned on. You can doublecheck this by clicking on "Network" in Explorer, and there may be a prompt at the top of the Explorer window that asks you to turn it on. The reason it may work on the 10.x.x.x network is because it may recognize that network as a Home or Work network, but the 172.x.x.x network as a public network. The settings are separate for each type of network.
When pinging from Fedora to Windows on the 172.x.x.x network, it's possible that the source IP of the ping packet is getting set to the IP address on the 10.x.x.x network. This may cause the packet to get dropped immediately by Windows since a packet arrived on the 172.x.x.x interface with a source IP that belongs to the subnet on another interface. This can be easily confirmed by tcpdump/wireshark on Fedora.
======== EDIT ========
So we have confirmed that when Fedora (172.124.16.128) pings Windows (172.124.16.39), the destination MAC address is set to 00:00:00:00:00:00, which is incorrect. The target MAC should be the MAC address of the network interface on Windows that has the IP address of 172.124.16.39 configured on it.
The process of resolving IP to MAC addresses is done by ARP (Address Resolution Protocol), and should happen automatically in the background. To debug why the MAC address isn't getting resolved properly, please clear all ARP cache on Fedora (Google how to clear ARP cache on Linux), start capturing packets, then see what happens with the ARP packets. If you have trouble understanding the packets, you can post them here, and I will take a look.