For those of us that need to connect to clients/partners that use the Cisco VPN utility, getting it to work on Linux can sometimes be a bit of a mission. Luckily the Open Source World always has one or more alternatives. In this case, ShrewSoft VPN.
This guide is loosely based on the this post but I was unable to complete the installation because of the following error:
hendri@techedemic: /var/tmp/ixgbe-4.1.2/src $ dmesg ......snipped...... [12270.405508] ixgbe: Unknown symbol vxlan_get_rx_port (err 0) [12428.182904] ixgbe: Unknown symbol vxlan_get_rx_port (err 0) [13448.131090] ixgbe: Unknown symbol vxlan_get_rx_port (err 0) [18947.596474] ixgbe: Unknown symbol vxlan_get_rx_port (err 0) [18975.603555] ixgbe: Unknown symbol vxlan_get_rx_port (err 0) ......snipped......
So, here follows the same guide, but with the missing steps I needed to complete the installation.
As a reference, I was running Kernel 3.13.0-20 before this.
Sometimes you might need to test whether a specific port is open in Linux based on your firewall rules. Without having to install specific software (e.g, telnet server for port 21) you can test this using netcat.
This can be handy if you need to prove to a service provider that they are blocking your ports.
Example, port 21
On the server side:
For ports under 1000 you must be root/sudo user
sudo netcat -l 21
On the client side
netcat [server ip] 21
It will look like nothing has happened. On the client side, just type some random words, e.g. “Hello World!” and hit [ENTER]. If the connection was successful, you should see the same words echoed on the server side.
To end the session you can either use CTRL+C on the server side (will kill both sides) or CTRL+D on the client side (will only kill the client side)
Please see Connect via RDP to Ubuntu 14.04 using XRDP for an updated version of this post.
If you need to connect to a Linux machine, and in the scope of this guide, Ubuntu 13.10 (I’m sure this guide should be fine for earlier versions as well), then your options include:
- Pure and simple SSH – The admin’s super tool! (just install openssh-server – works every time!)
- VNC – I don’t like this method because you need to install software on your client AND server
- XRDP – This still involves VNC to some degree but you can use the normal Windows Remote Desktop Client
The latter is the one I’ll guide you through here. Continue reading
WMIC is a useful tool in the world of remote management, and more specifically tracking the performance of Windows machines, so I thought I’d show how I got it installed on Ubuntu 12.04 LTS – Desktop. This should work fine on most other versions of Ubuntu as well, but please comment if it did not.
By default, when you install snmpd (this was tested on Ubuntu 10.04, not sure about other Linux variants), the daemon is set to listen only on 127.0.0.1 (localhost)
If you run chech the process, you can see this:
techedemic@demo:/etc/default$ ps awux | grep snmp snmp 32753 0.3 2.0 47916 4948 ? S 09:29 0:00 /usr/sbin/snmpd -Lsd -Lf /dev/null -u snmp -g snmp -I -smux -p /var/run/snmpd.pid 127.0.0.1 sintrex 32757 0.0 0.3 7624 904 pts/0 S+ 09:29 0:00 grep --color=auto snmp
To allow access to any machine from outside (make sure your company security policies allow for this), you need to edit the /etc/default/snmpd file as follows:
Sometimes you might have to activate some interfaces in your Ubuntu Server (or desktop for that matter) that you could use for your VMWare server, or to do a tcpdump for some promiscious traffic coming from a mirrored port…or hell’s bells, whatever…you just need it active without any IP assigned – and you need it to be up even if the box restarts.
If you want to do it, here’s how …