This is howto install sslexplorer (SSL VPN over web) running on top of Centos 6. Those who don’t know yet what sslexplorer actually is, please read it here. Basically, sslexplorer will allow you to connect to your corporate network from external (RDP, file transfer, reverse proxy and etc) via a simple web browser. You can get the opensource one from sourceforge.net though I never get it working by using the one coming from sourceforge. Fortunately, I got my copy (version 1.0.0 RC16) from 3SP before it been taken by Barracuda in 2008 and till now, I’m still using it for my personal use especially fro RDP. Numerous installation has been done previously by me on top of Slax, Slackware, Fedora and the latest one is Centos 6.

Requirement

• sslexplorer-linux-1_0_0_RC16.sh
• Java run time
• X Desktop

Steps:

• Download sslexplorer,
• Locate sslexplorer installer from Centos GUI,
• Open terminal
• Run the installer #sh sslexplorer-linux-1_0_0_RC16.sh,
• Select yes to install java run time,
• Setup

Setup: (Run via Wizard)

• Create new certificate
• Create password for new certificate
• Give details of your certificate
• Configure user database
• Configure Web Server
• Configure proxy (if any)
• Summary
• Install
• Complete and launch it (http://locahost:port) - default 28080

Download RDP Extension:

RDP extension only can be downloaded from 3SP extension store. Unfortunately, RC16 and RC17 (sourceforge) no more able to connect to this store probably due to Barracuda restriction. Alternatively, you can create the extension on your own or download the one come from adito and upload it to your sslexplorer server.

• Download RDP extension from adito,
• Upload the extension to sslexplorer server,
• Create RDP application shortcut

Configure RDP Shortcut

• Click “Resources” > “Application”
• Click “Create  Application Shortcut”
• Choose “Microsoft RDP Client”
• Give application name and description (add to favorite)
• Give your back-end RDP server IP and port
• Give appropriate permission
• Finish

To start your first RDP’s session, just click your favorite RDP shortcut under “resources” > “application” and then just wait until your RDP terminal is open.

p/s: Please make sure your browser has java run time installed.

ariyossss

This is howto install VMware Tools for Centos 6 (kernel 2.6.32-220.el6.x86_64) which is running on top of ESX 4.0. However, I can’t guarantee that the same step is working for ESXi 5.0 U1. Feel free to ask if you require some assistance from me.

Requirement

• Kernel-header 2.6.32-220.el6.x86_64)
• GCC compiler #yum install gcc

Steps

• Just initiate VMware Tools Install from vSphere client,
• Right click & choose to open it via package installer,
• Install gcc #yum install gcc
• Download kernel-devel from the given url above
• Install kernel-devel #rpm -i kernel-devel-2.6.32-220.el6.x86_64.rpm
• Configure VMware Tools #vmware-config-tools.pl
• Give your kernel header directory (/usr/src/kernels/2.6.32-220.el6.x86_64)
• Then, next and next till finished

Notes:

• Don’t use yum when installing your kernel-devel else, you will get a different one (i.e 2.6.32-279.el6.x86_64)
• Please choose a default answer (NO) when running to build “vmmemctl”
• Please choose “Yes” for the rest (i.e vmci, vmnet3, pvscsi & etc)

ariyossss

Sigh.. while setting up a new Vyatta from scratch today, I have noticed that version 6 is quite different from the old one. Therefore, I have to record all new nat commands here as for my future reference:

1)DHCP SERVER

• #set service dhcp-server shared-network-name ZEN-USER subnet 192.168.1.0/24 start 192.168.1.100 stop 192.168.1.200
• #set service dhcp-server shared-network-name ZEN-USER subnet 192.168.1.0/24 default-router 192.168.1.241
• #set service dhcp-server shared-network-name ZEN-USER subnet 192.168.1.0/24 dns-server 10.1.1.10

2)NAT

• #set nat source rule 5 outbound-interface eth0
• #set nat source rule 5 source address 192.168.1.0/24
• #set nat source rule 5 translation address masquerade
• #show nat source
• #commit
• #save

ariyossss

Recently, I’m a bit surprised when one of my colleague has told me that some of the VMs had an error message related to a snapshot after we had migrated it from VI3 to vSphere 5. When we did some investigation, we have found out that the default snapshot location now wasn’t pointing to VM working directory. Instead, the snapshot file that has been created was saved into base vmdk folder.

Due to my customer’s requirement in 2008, all VMs configuration file (.vmx) has been stored separately from it base virtual disk(vmdk) LUN. Of course there was some free space left in the (vmx) datastore for keeping the snapshot file but not for vmdk LUN. The outcome was pretty obvious, one by one the VM will pop-up an error message related to “no free space” left in the datastore whenever we had performed VM snapshot.  Since we weren’t aware and prepare for this, the only thing that we can do is to change the snapshot location back to virtual machine home folder(.vmx) by adding one parameter to individual VM as follows.

• Power off the VM
• Edit VM setting
• Go to Option tab
• Advance (Parameter) and
• Add row and then put “snapshot.redoNotWithParent”
• Set the value to “true”
• Power on the VM

Notes:

• Existing snapshot will be migrated to base vmdk once you performed storage vMotion
• “workingDir” parameter is no more valid for vSphere 5

ariyossss

Want agentless and free monitoring tools which can monitor your customer front-end servers (ie. web, email)? then PHP Server monitor is one of your best choice. It’s a very light tools built from php scripts (KB size) and must be installed on any web server which has an internet connection. With this tools at least you can be notified earlier every time when one of the server goes down especially during midnight.

1.Installation

The installation is pretty straight forward but you have to must make sure that your php installation must compiled with a curl module. Then some tweak are needed for the script in order to make sure email notification is working especially the phpmailer.class.php.

• Extract and upload the script to your www root
• create new mysql database
• create config.php with appropriate parameters
• Install it by launching ../install.php from your browser

2.Setup

Any user can be created though at this moment there is no AD/LDAP integration. One more thing, there is no authentication page and anyone who knows the url, at anytime just can add their own server to the list. So just beware..

• Add user
• Add server with appropriate port number,

3.Optional (Email Notification)

My Fedora 13 is require some hard work for the sendmail especially when you try to run m4. So, what I did was, I’ve started with just a few lines of sendmail.cf and add additional define/feature into it one by one. I’m using gmail smtp as a smart host and it’s working fine as expected.

• Enable email monitoring in php server monitor config
• Configure sendmail with smart host
• Cronjob to check server status

Within hours, now I have a tools which can monitor a list of external servers and send an email alerts every time when the server goes down. Proactive monitoring? Not a big deal..
ariyossss