Month: December 2012

How to add a disk to LVM

Posted on by admin

Suppose the Disk is /dev/sdb, the second scsi disk,

   fdisk /dev/sdb
   create as many partitions as you need using command n
   Label them with command t as 8e for making it Linux LVM
   Write and Exit with the command w.

Format the partitions you require using mkfs command

   mkfs -t ext3 -c /dev/sdb1

LVM commands

   pvcreate /dev/sdb1
   vgextend VolGroup00 /dev/sdb1
   lvextend -L 15G /dev/VolGroup00/LogVol01 ;for extending LogVol to 15GB
   lvextend -L+1G /dev/VolGroup00/LogVol01 ;for adding one more GB to Logical Volume LogVol01
   lvextend -l +100%FREE /dev/VolGroup00/LogVol01


Next you shall need to resize the filesystem.


   resize2fs -l /dev/VolGroup00/LogVol01


Thats it finished Njoy  🙂 !

        

        


	






    


        
		
Test if memcache is installed in php from bash line

        

            Posted on  by admin        

    


    
    

                

                        
php -i | grep -i memcache


Short and sweet

sample output :


memcache

memcache support => enabled

memcache.allow_failover => 1 => 1

memcache.chunk_size => 8192 => 8192

memcache.default_port => 11211 => 11211

memcache.default_timeout_ms => 1000 => 1000

memcache.hash_function => crc32 => crc32

memcache.hash_strategy => standard => standard

memcache.max_failover_attempts => 20 => 20

memcached

memcached support => enabled

libmemcached version => 0.50

Registered save handlers => files user memcache memcached


Njoy 🙂

        

        


	






    


        
		
Using Expect to automate an scp filetransfer

        

            Posted on  by admin        

    


    
    

                

                        
Sometimes you know passwords but are not ion a position to use shared keys. Solution is using expect to pass the password from a script read or a comman line parameter.


** NOTE Passwords in command lines are a really bad idea since you can see them in the history / ps -ef so best is to read from stdio and pass as a parameter.


 


 


#!/usr/bin/expect
spawn scp [lindex $argv 0] root@192.168.8.117:/vmfs/volumes/datastore1/
######################
expect {
-re "Password:" {
exp_send "[lindex $argv 1]\r"
}
}
interact





        

        


	






    


        
		
ESXi 5.1 : Fixing ‘Failed to deploy OVF package: The task was canceled by a user.

        

            Posted on  by admin        

    


    
    

                

                        
Where I work, we love using OVA templates to speed up our deployment of virtual machines. I recently upgraded one of my servers to ESXi 5.1 (which also required an update to vSphere). ESXi 5.1 provides support for Windows 8 and Server 2012, which is incredibly useful. However, whilst building OVA templates for these operating systems, I stumbled across an issue.


I ran through the ‘New Virtual Machine’ wizard, selecting Windows 8 (or Server 2012), leaving all settings default. Installed my operating system, and made the required customisations, shutdown the machine and exported an OVA template through vSphere – excellent, how easy!


However, whilst trying to re-deploy the OVA to the ESXi 5.1 host, through the ‘Deploy OVA template’ wizard, it failed immediately after completing the wizard (right before it shows the deployment progress bar). Now, I have a particular hate for misleading error messages, and this one seems to fall right in-to that category –


Failed to deploy OVF package: The task was canceled by a user.


How misleading. I, or any other user, certainly didn’t cancel the task. So what happened? I took a look through the (horrendous) hostd.log on the ESXi box and found absolutely nothing of any value.


Frustrated by the inability to redeploy a template I spent so long preparing, I broke open the OVA template and took a look inside. There were three files with different extensions,


    

  • .ova – OVF descriptor, written in XML, which describes the hardware requirements
    • 

  • .mf – contains SHA1 checksums of the .OVA and .VMDK
    • 

  • .vmdk – the virtual hard disk for the virtual machine.
    • 



I immediately discarded (renaming to .mfx will do the trick) the .mf. If you modify the .ova and don’t update the .mf, it’ll complain that the checksum is invalid. Removing this file seems to prevent vSphere from checking the checksums, which is useful, seeing as we want to poke around the .ova. After fiddling around inside the .ova, I stumbled across the following line…




<rasd:ResourceSubType>vmware.cdrom.iso</rasd:ResourceSubType>


Changing the above line, to read…


<rasd:ResourceSubType>vmware.cdrom.atapi</rasd:ResourceSubType>


…appears to have fixed my deployment issues. Perhaps changing the ‘CD Drive Device type’ in the virtual machine’s settings would’ve fixed it. But by that point, I had already exported the OVA and deleted the source virtual machine.


Hopefully someone will stumble across this one day, and it’ll save them a few hours!

        

        


	






    


        
		
SVN checkout fails to authenticate

        

            Posted on  by admin        

    


    
    

                

                        
When running:


svn checkout https://mysvn.mydomain.com:8443/svn/Linux/trunk/scripts/ –username *** –password ‘****’


I got :


WARNING: gnome-keyring:: couldn’t connect to: /tmp/keyring-fTq763/pkcs11: No such file or directory

Password for ‘default’ GNOME keyring: *****

svn: OPTIONS of ‘https://mysvn.mydomain.com:8443/svn/Linux/trunk/scripts’: authorization failed: Could not authenticate to server: rejected Basic challenge (mysvn.mydomain.com:8443)


Problem could be damaged keyring or wrong keyring password.


To fix quickly :


pkill keyring


re-run the checkout.


Voila ! you get a new keyring and the process works. Checkout goes through.


Njoy 🙂


p.s.


As a desparate measure :


mv /usr/bin/mate-keyring-daemon /usr/bin/mate-keyring-daemon.rubbish

        

        


	






    


        
		
SSH through HTTP proxy

        

            Posted on  by admin        

    


    
    

                

                        


This article explains how to connect to a ssh server located on the internet from a local network protected by a firewall through a HTTPS proxy.


Requirement are :


    

  • 

    Your firewall has to allow HTTPS connections through a proxy
    

    • 

  • 

    You need to have root access to the server where ssh is listening
    

    • 





Configure the ssh server




The ssh daemon need to listen on 443 port. To accomplish this, just edit this file (on debian system) /etc/ssh/sshd_config and add this line :


Port 443


Then restart the daemon :


sudo /etc/init.d/ssh restart




Configure the client




I suppose you are on a Linux system (debian for example). First you have to compile the connect binary which will help your ssh client to use proxies (HTTPS in our case). Then you have to configure your ssh client to tell him to use HTTPS proxy when he tries to connect to your ssh server.


    

  1. 

    Install the connect software :
    

      

    • 

      On debian system, just install the connect-proxy package :
      

      sudo apt-get install connect-proxy
      

      

      • 

    • 

      On other Linux systems, you have to compile it :
      

      cd /tmp/
wget http://www.meadowy.org/~gotoh/ssh/connect.c
gcc connect.c -o connect
sudo cp connect /usr/local/bin/ ; chmod +x /usr/local/bin/connect
      

      

      • 

    

    2. 

  2. 

    Configure your ssh client. Open or create your ~/.ssh/config file and add these lines :
    

    ## Outside of the firewall, with HTTPS proxy
Host my-ssh-server-host.net
  ProxyCommand connect -H proxy.free.fr:3128 %h 443
## Inside the firewall (do not use proxy)
Host *
   ProxyCommand connect %h %p
    

    

    3. 

  3. 

    Then pray and test the connection :
    

    ssh my-ssh-server-host.net
    

    

    4. 





SSH to another server through the tunnel




For example to connect to in ssh github.com :


Host github.com
  ProxyCommand=ssh my-ssh-server-host.net "/bin/nc -w1 %h %p"