I am trying to use a single IP as a "floating IP" by assigning it to a secondary interface eth1 between 2 VMs. The primary interface eth0 has 2 different IPs for both VMs. Only one of the VMs will have the IP assigned to eth1 at any given time. If we have any issues with the primary VM we will unassign the IP from eth1 of the primary VM and reassign it to the secondary VM.
We are unassigning and assigning the IP using -
/sbin/ip addr ${ACTION} ${IP} dev ${INTERFACE}
However once we unassign the IP from eth1 of the primary VM and assign it to eth1 of the secondary VM I am unable to ssh to the secondary VM right away. I get a -
ssh: connect to host x.x.x.x port 22: Connection timed out
After about 15 mins some cache somewhere gets cleared and then I am able to ssh to the secondary box.
Have the following setting already updated in sshd_config and sshd has been restarted.
GSSAPIAuthentication no
UseDNS no
We are using Redhat 7.6
Any help in the troubleshooting what could be causing the delay in ssh'ing to the secondary box is much appreciated!
Thanks!
Your issue is with your network gear and the clients arp tables.
After you change the address check your arp tables with arp -a on Linux and show ip arp (Cisco gear). You will see the old MAC address maps to the old server IP.
After you change ip addresses send a gratuitous arp and that will force everything to update.
Assume your ethernet address is 10.0.10.1 and you are using eth1.
yum install arping -y
arping -A -I eth1 10.0.10.1
This very similar to what VMware does when you VMotion a VM to another host. It sends an RARP to notify the network the MAC address has moved to different a port.
EDIT: Also note, in older RHEL ver ifup-eth script used the arping tool to send a GARP. That means I might also try ip link set eth1 down and ip link set eth1 up see if that works.
This issue got resolved. We had to update the arp neihbor cache to get this to work so incorporated that into our script.
Iam using vmware workstation12. I have a 2 vm and I installed Ubuntu in it.
The ip address changes automatically in the ubuntu.Last week the IPADDRESS in the first vm was 192.168.56.1 and in the second vm was 192.168.56.2.
But today I got changed to 192.168.56.3 and 192.168.56.4.
Because of this change I need to change lot of thing in my hadoop setup like ssh and name node configuration and lot of things.
Please help me to assign fixed ipaddress to vm.
This article would help: https://communities.vmware.com/message/1888335
So, basically, it tells you how to configure the DHCP service for VMWare to mapping IP address with MAC address of the guest VM, therefore the guest VM will always been assigned with the IP address you've specified.
It is like adding this section to the end of vmnetdhcp.conf file (On the host Windows machine. For other OS, such as VM Fuse on macOS or VMWare on Linux or ESXi, the file name/path could be varial, but the setting are expect to be similar):
host Win81x86A {
hardware ethernet 00:0C:29:56:4F:A9;
fixed-address 192.168.213.10;
}
In addition to this, which the article didn't introduce, there's other steps if it doesn't take effect (On Windows):
Make sure you've configured the right configuration file. On Windows, Config the configuration file:
%%ALLUSERDATA%%\Vmware\vmnetdhcp.conf
Stop the "VMware DHCP Service" and "VMware NAT Service".
Clean up the ".leases" file:C:\ProgramData\Vmware\vmnetdhcp.leases
Restart the "VMware DHCP Service" and "VMware NAT Service"
Start VMWare and run the VM. Or, if already running, issue a DHCP renew command (Linux: sudo dhclient -rv; sudo dhclient -v)
It should be working now.
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I have a Ubuntu VM running on my Windows 7 machine. How do I set it up so that I can access the webserver externally through SSH?
I found steps (Setup SSH access between VirtualBox Host and Guest VMs) to be able to ssh to my guest from my host, but that still leaves me with the problem of accessing it through my router.
I suppose that I could install an SSH server on my Windows machine and then tunnel a few times (though I'm not 100% sure what to use in terms of local, dynamic, etc. or how to set up multiple tunnels?), but is there a way to make the VM directly accessible to my router so I could directly port forward to it?
The best way to login to a guest Linux VirtualBox VM is port forwarding. By default, you should have one interface already which is using NAT. Then go to the Network settings and click the Port Forwarding button. Add a new Rule. As the rule name, insert "ssh". As "Host port", insert 3022. As "Guest port", insert 22. Everything else of the rule can be left blank.
or from the command line
VBoxManage modifyvm myserver --natpf1 "ssh,tcp,,3022,,22"
where 'myserver' is the name of the created VM. Check the added rules:
VBoxManage showvminfo myserver | grep 'Rule'
That's all! Please be sure you don't forget to install an SSH server in the VM:
sudo apt-get install openssh-server
To SSH into the guest VM, write:
ssh -p 3022 user#127.0.0.1
Where user is your username within the VM.
Change the adapter type in VirtualBox to bridged, and set the guest to use DHCP or set a static IP address outside of the bounds of DHCP. This will cause the Virtual Machine to act like a normal guest on your home network. You can then port forward.
Keeping the NAT adapter and adding a second host-only adapter works amazing, and is crucial for laptops (where the external network always changes).
http://muffinresearch.co.uk/archives/2010/02/08/howto-ssh-into-virtualbox-3-linux-guests/
Remember to create a host-only network in virtualbox itself (GUI -> settings -> network), otherwise you can't create the host-only interface on the guest.
You can also use a Bridged Network (or "Bridge Adapter", in newer versions) in network settings. This will put your VM in a VLAN with your machine. So you can just ssh into the VM like this.
ssh user#IP_OF_VM
How to do host-only network (better than bridged) for Solaris 10 and Ubuntu 16.04
Add Host-only interface
Virtualbox > File > Preferences > Network > Host-only Networks > Add
Shutdown vm.
VM's Settings > Network. First adapter should be Nat, second Host-only.
Start cmd.exe and run ipconfig /all. You should see lines:
Ethernet adapter VirtualBox Host-Only Network:
...
IPv4 Address. . . . . . . . . . . : 192.168.59.1
Second adapter in guest should also be in 192.168.59.*.
Start VM.
Solaris 10
Check settings ifconfig -a. You should see e1000g0 and e1000g1. We are interested in e1000g1.
ifconfig e1000g down
ifconfig e1000g 192.168.56.10 netmask 255.255.255.0 up
Check from host if this interface is reachable: ping 192.168.56.10
Preserve those settings upon reboot
# vi /etc/hostname.e1000g1
192.168.56.10 netmask 255.255.255.0
# reboot
Configure ssh service (administering) to login as root (not adviced)
Check if ssh is enabled
# svcs -a | grep ssh
online 15:29:57 svc:/network/ssh:default
Modify /etc/ssh/sshd_config so there is
PermitRootLogin yes
Restart ssh service
svcadm restart ssh
From host check it
ssh root#192.168.56.10
Ubuntu 16.04
List interfaces:
ip addr
You should see three interfaces like lo, enp0s3, enp0s8. We will use the third.
Edit /etc/network/interfaces
auto enp0s8
iface enp0s8 inet static
address 192.168.56.10
netmask 255.255.255.0
Then sudo ifup enp0s8. Check if enp0s8 got correct address. You should see your ip:
$ ip addr show enp0s8
...
inet 192.168.56.10/24 brd 192.168.56.255 scope global secondary enp0s8
If not, you may run sudo ifdown enp0s8 && sudo ifup enp0s8
https://superuser.com/questions/424083/virtualbox-host-ssh-to-guest/424115#424115
In order to ssh to a Ubuntu VM running in VirtualBox from your host machine, you need to set up two network adapters for the VM.
First of all, stop the VM if not yet.
Then select the VM and click the Settings menu in the VirtualBox toolbar:
Set up Adapter 1
Set up Adapter 2
(Note: you don't need to set up any port forwarding.)
That's it. Once set up, you can start your VM. In your VM, the network configuration will look like below and you'll have Internet access too:
Also in your host machine, you can ssh to your VM:
Be sure that the SSH server has been installed and up running in the VM.
$ ps aux | grep sshd
root 864 0.1 0.5 65512 5392 ? Ss 22:10 0:00 /usr/sbin/sshd -D
If not, install it:
$ sudo apt-get install openssh-server
Also for your information:
My VirtualBox version: 5.2.6 r120293 (Qt5.6.2), 2018
My Ubuntu version: Ubuntu 16.04.3 LTS
My host machine: Windows 10
SSH Back to Your Home / Office VirtualBox Guest Machine From The INTERNET
The answers provided by other users here : How to SSH to a VirtualBox guest externally through a host?
... helped me to accomplish the task of connecting from out on the internet to my home computer's guest machine. You should be able to connect using computers, tablets, and smart phones (android, IPhone,etc). I add a few more step in case it might be helpful to someone else:
Here is a quick diagram of my setup:
Remote device ---> INTERNET --> MODEM --> ROUTER --> HOST MACHINE --> GUEST VM
Remote device (ssh client) ---> PASS THRU DEVICES ---> GUEST VM (ssh server)
Remote device (leave ssh port 3022) ---> INTERNET --> MODEM --> ROUTER (FWD frm:p3022 to:p3022)--> HOST MACHINE (FWD frm:p3022 to:p22) --> GUEST VM (arrive ssh port 22)
The key for me was to realize that ALL connections was PASSING-THROUGH intermediary devices to get from my remote PC to my guest virtual-machine at home --Hence port forwarding!
Notes:
* Need ssh client to request a secure connection and a running ssh server to process the secure connection.
I will forward the port 3022 as used in the chosen answer from above.
Enter your IPs where needed (home modem/router, host IP, guest IP,etc.), Names chosen are just examples-use or change.
1.Create ssh tunnel to port 3022 on your modem's IP / router's external IP address.
ssh client/device possible commands: ssh -p 3022 user-name#home_external_IP
2.Port forward = we are passing thru the connection from router to host machine
Also make sure firewall /IPtable rules on router is allowing ports to be forward (open if needed)
Router's Pfwd SCREEN required entries: AppName:SSH_Fwd, Port_from: 3022, Protocol:both (UDP/TCP), IP_address:hostIP_address, Port_to:3022, everything else can be blank
DD-WRT router software resources / Info:
DD-WRT Port_Forwarding
DD-WRT Static_DHCP
3.Host Machine Firewall: open port 3022 #so forwarded port can pass thru to guest machine
Host Machine: Install VirtualBox, guest additions, and guest machine if not done already
Configure guest machine and then follow the Network section below
I used VirtualBox GUI to setup guest's network- easier than CLI
If you want to use other methods refer to : VirtualBox/manual/ch06.html#natforward
4.Some suggest using Network Bridge adapter for guest = access to LAN and other machines on your LAN. This also pose an increase security risk, because now your guest machine is now exposed to LAN machines and possibly the INTERNET hackers if firewall not setup properly. So I selected Network adapter attached to NAT for less exposure to bridged security risks.
On the guest machine do the following:
Guest Machine VirtualBox Network settings: Adapter 1: Attached to NAT
Guest Machine VirtualBox Port Forwarding Rule: Name:External_SSH, Protocol:TCP, Host Port: 3022, Guest Port 22, Host&guest IPs:leave blank
click on advance in Network section then click on Port forwarding to enter rules
Guest Machine Firewall: open port 22 #so ssh connection can enter
Guest Machine: Make sure that ssh server is installed, configured properly, and running
LINUX test to see if ssh server running w/command: sudo service ssh status
Can check netstat to see if connection made to port 22 on the guest machine
Also there are different ssh servers and clients depending on platform using.
wikipedia/Secure_Shell
wikipedia/Comparison_of_SSH_servers
wikipedia/Comparison_of_SSH_clients
For Ubuntu Users:
ubuntu community: SSHOpenSSH/Configuring
ubuntu/community: OpenSSH/Keys
That should be it. If I made a mistake or want to add anything -feel free to do so-- I am still a noob.
Hope this helps someone. Good luck!
For Windows host, you can :
In virtualbox manager:
select ctrl+G in your virtualbox manager,
then go to network pannel
add a private network
make sure that activate DHCP is NOT selected
In network management (windows)
Select the newly created virtualbox host only adapter and the physical network card
Right-Click and select "Make bridge"
Enjoy
You can also initiate a port forward TO your HOST, OR ANY OTHER SERVER, from your Guest. This is especially useful if your Guest is 'locked' or can't otherwise complete the ModifyVM option (e.g. no permission to VBoxManage).
Three minor requirements are 1) you are/can log into the VirtualBox Guest (via 'console' GUI, another Guest, etc), 2) you have an account on the VirtualBox HOST (or other Server), and 3) SSH and TCP forwarding is not blocked.
Presuming you can meet the 3 requirements, these are the steps:
On the Guest, run netstat -rn and find the Gateway address to the default route destination 0.0.0.0. Let's say it's "10.0.2.2". This 'Gateway' address is (one of) the VirtualBox Host virtual IP(s).
On the Guest, run ssh -R 2222:localhost:22 10.0.2.2 where "10.0.2.2" is the VirtualBox server's IP address -OR- any other server IP you wish to port forward to.
On the Host, run ssh 10.0.2.2 -p2222 where 10.0.2.2 is the default gateway/VBHost virtual IP found in step 1. If it is NOT the VirtualBox host you are port forwarding to, then the command is ssh localhost -p2222
Follow below steps to login to your ubuntu VM running in virtual box from the host machine using putty (Without port forwarding):
On Virtualbox manager select the vm, click on settings icon. Then go Networks and enable two adaptors as below:
Adaptor 1 (For internet access): Attached to -> NAT, Advanced -> Check the cable connected.
Adaptor 2: Attached to -> Host only adaptor, Advanced -> Check the cable connected and Promiscuous mode -> Allow all.
Start the ubuntu vm.
Login to the VM as root.
Edit the file '/etc/network/interfaces' as below and save it:
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto eth1
iface eth1 inet dhcp
Restart the VM.
Login to the VM and run below command to check the IP allocated to eth1:
ifconfig
Use this IP to open putty session for the VM.
A good explanation about how to configure port forwarding with NAT is found in the VirtualBox documents:
http://www.virtualbox.org/manual/ch06.html#natforward
Ubuntu 18.04 LTS
Configuration with bridged to see the server ip, and connect without "port forwarding"
VirtualBox > right click in server > settings > Network > enable adapter 2 > select "bridged" > Promiscuous mode: allow all > Check the cable connected > start server
On ubuntu server, edit sudo nano /etc/netplan/*init.yaml file,
My sample file:
network:
ethernets:
enp0s3:
addresses: []
dhcp4: true
enp0s8:
addresses: [192.168.0.200/24]
dhcp4: no
dhcp6: no
nameservers:
addresses: [8.8.8.8, 8.8.4.4]
version: 2
Commands that will help you
nano /etc/netplan/file.yaml # file to specify the rules of network
reboot now # restart ubuntu server right now
netplan apply # do after edited *.yaml, to apply changes
ifconfig -a # show interfaces with ip, netmask, broadcast, etc...
ping google.com # to see if there is internet
Configure Static IP Addresses On Ubuntu 18.04 LTS Server - with NetPlan
Simply setting the Network Setting to bridged did the trick for me.
Your IP will change when you do this. However, in my case it didn't change immediately. ifconfig returned the same ip. I rebooted the vm and boom, the ip set itself to one start with 192.* and I was immediately allowed ssh access.
On secure networks setting your network to bridge might not work. Administrators could only allow one mac address per port or even worse block the port should the switches detect multiple macs on one port.
The best solution in my opinion is to set up additional network interfaces to handle additional services you would like to run on your machines. So I have a bridge interface to allow for bridging when I take my laptop home and can SSH into it from other devices on my network as well as a host only adapter when I would like to SSH into my VM from my laptop when I am connected to the eduroam wifi network on campus.
Use NAT network adapter and Add port forward. Mention actual host ip.Do not use 127.0.0.1 or localhost.