Nuffnang

Tuesday, August 21, 2012

Security in the Cloud


Conventional infrastructure security controls designed for dedicated hardware do not always map well to the cloud environment.


Public Cloud architectures must have well-defined security policies and procedures in place.


1. Integrated Cloud Security - VLAN approach

Cloud environments should take this same approach and segment virtual machines by VLANs through Port Group configurations.

The concern in cloud environments is that IPS systems provide limited visibility to inter-virtual machine traffic flows. These are the flows between virtual machines on the same VLAN.

By default, those traffic flows are not visible to traditional network-based security protection devices located in the datacenter network.

Administrators must make specific architecture and configuration decisions either to make the virtualization solution work with current security tools or to integrate security appliances into the virtualization architecture.


2. Cloud Burst Security

One of the primary advantages of cloud computing is that enterprises can move applications that consist of several virtual machines to the cloud provider when the physical environment requires additional processor or compute resources.

These bursting virtual machines need security policies and baseline histories to move with them. When a virtual machines moves, if the security policy does not accompany it, that virtual machines becomes vulnerable. In addition, when virtual machines move, they lose their performance histories and administrators must re-evaluate the virtual machine performance baselines.


3. Compliance Concerns – system, vm, all cloud log must keep in safe location

The auditing community is aware that current practices for auditing cloud environments are inadequate. As compliance grows in importance, enterprises implementing clouds need to satisfy their auditors’ concerns; especially since creating an identity for an individual virtual machine and tracking that virtual machine from creation to deletion creates challenges for even the most mature virtualized environments. Virtual machine sprawl-- when the number of virtual machines being created is growing more quickly than an enterprise’s ability to manage them-- adds complexity.


4. Defense in Depth

By providing security services from within the cloud provider infrastructure, enterprises are able to deploy security policies and rules between each virtual machine (or between virtual machine centers) as they would in the physical world. A feature of the cloud provider infrastructure is that enterprises can maintain corporate security policies and the data collected about them with the virtual machines. This allows them to enforce security services in the enterprise and the cloud provider consistently

Sunday, August 12, 2012

Offsite Backup Solutions : Positives & Negatives


Positives

Negatives

Traditional Tape


- Low cost

- Familiar Process

- Somewhat Simple

- Long Retention

- Supported by most backup software

- Prone to Breaking

- Slow

- Can be stolen/lost

- Requires people

- Tapes go bad

- Requires a compatible tape drive for future restores

Software Replication

- Disk to Disk based

- Fast Backups and Restores

- Hardware agnostic

- Can work with Hardware Appliances

- No user intervention required to replicate

- Fairly Cheap

- Requires Bandwidth

- Can be complex

- Resource Intensive

- May effect other services like VoIP, Remote workers etc

Appliance (Hardware) Replication

- Disk to Disk based

- Fast Backups and Restores

- Software Agnostic (in some cases)

- No user intervention required to replicate

- Deduplication and Compression

- Requires Bandwidth

- Still Requires Backup Software

- Can be complex

- Expensive

- Can be vendor specific

- May effect other services like VoIP, Remote workers, etc.

Virtualization Replication

- Quick DR Recovery

- Integrated

- Snapshot Technology

- Change Block Tracking

- Requires Bandwidth

- Can be complex

- Expensive

- Can be vendor specific

- May affect other services like VoIP, Remote workers, etc.

Monday, August 6, 2012

Linux: Benefit of Virtualization

Virtualization has a lot of benefits: it can help reduce costs by requiring less hardware and improving overall energy efficiency. It also produces higher performance with many of the best enterprise applications, including Oracle and SQL Server. That doesn't mean that virtualization doesn't have its difficulties, however, especially when it comes to Linux. Here are a few tips that can help you get the most out of your Linux virtualization.

Make use of virtual machine templates
Templates are a great way to increase efficiency in a virtual machine. They allow the administrator to quickly and easily deploy new virtual machines without worrying about consistency. At its simplest, a template is simply a converted virtual machine that includes all the guest additions, updates and patches required for deployment. If you need to add more updates and patches, simply convert the template back to a virtual machine, apply them, then move it back to template status.

Virtual machines can be disposable
Virtualization is an excellent choice for disposable systems that could be dangerous to the rest of your network. For more information on virtualization, please click here. They work well when you need to test your defenses against malicious software, when you want to find out what a virus could potentially do to your systems, or for creating honeypots to counteract unauthorized use attempts.

Just remember to disable the virtual machine's network interface to keep any and all threats on the virtual machines and away from other virtual or real-life systems. Even though your virtual machines are dealing with Linux, they could have access to Windows machines, which are far more susceptible to malicious attacks.

Use the right hardware
It can be tempting to install your virtual machines on any piece of hardware you have lying around, especially since Linux can be so hardware-adaptable. This usually ends up being a mistake, however. For any medium to large-scale implementation, make sure you build high quality virtual hosts with 64-bit CPUs and multiple processors, enough memory to handle multiple virtual machines, large amounts of hard disk space and multiple network interfaces. If you must use older hardware, make sure that you can at least meet processor requirements and use more than 8 GB of memory.

Adhere to standard security rules
A virtual machine is just like a physical one when it comes to security. That means that you need to apply the same security rules to every computer in your network, even if it's one that doesn't physically exist. While Linux machines tend not to be vulnerable to viruses in the same way a Windows virtual box might be, they can still be attacked by individuals. The amount of malicious software that can attack Linux machines is also on the rise. Make sure you use firewalls and anti-malware programs, disable or removed all unused services, and allow only the secure versions of all protocols.

Keep disk images separate for better performance
If you find that one or more of your virtual machines are experiencing trouble with performance, consider putting each disk image in a separate storage location. Put data storage, operating systems and logs at separate logical unit numbers, or LUNs. By separating these disks, you'll increase speed and performance while reducing bugs and slowdowns.

Mimic physical networks
If you're moving a physical system to a virtual one, don't make big changes to the infrastructure. Be sure to set up a network that mimics the physical one in layout and design, creating virtual private and local area networks, as well as virtual switches. If your physical network is well-designed, this should produce an efficient migration with no unpleasant surprises.

Keep hosts updated
In addition to making sure your physical hosts are set up properly, you must also keep them up to date for best performance. Make sure that all hardware gets the latest updates to BIOS from the manufacturer's website. Patch the host systems, too, not just the virtual machines themselves. Set your host systems up to get regular updates from the appropriate repositories, and then let them apply the patches themselves. A regular update policy will help you reduce downtime due to updating and prevent the exploitation of known vulnerabilities.

Save before major updates
While virtual machines make it a lot easier to make changes to your server environment, they also make it easier to make those changes irresponsibly. You never know when a major adjustment will cause something to stop working correctly. Instead of plunging right in, clone or snapshot the current state of your virtual machine before you make the changes. While this is hard to do for every virtual machine if you have a large setup, you can still do it for the most critical machines. Cloning or snapshotting is faster and more efficient than a traditional backup and will help you prevent irreversible mistakes.

Skip the screensaver
While screensavers are traditional and installed on most operating systems, they're a bad choice for virtual machines. That's because they use up system resources that could be channeled to a different machine. Uninstall or turn off all screensavers from your virtual machines by default. If you absolutely need some kind of screensaver to protect privacy, if screens are left on, choose screen blanking, not an animated option.

Remember to remove disk images
It's easy to forget to remove the virtual disk images when you get rid of a virtual machine. Leaving these in place, however, is a mistake. By failing to remove these disk images, you're using up important disk space. You're also filling your storage systems with useless virtual clutter. By making sure you have removed all virtual disks whenever you remove a virtual machine, you reduce the risk of “orphans.” Just in case, take the time to scan your storage using a shell script that will detect and remove any orphaned disks.

Moving to virtual machines is a sound strategy for a wide range of organizations, but you have to do it correctly. By paying attention to these tips, you'll keep your Linux virtual machine environment running smoothly and efficiently."

Wednesday, August 1, 2012

Windows 7: Burn DMG Files

  • First you have to download this small tool called dmg2img. That will convert your Disk Image (DMG file) to an IMG file, which can be read and burnt directly by Windows 7 for instance.
  • In the next step you locate your directory where you saved dmg2img.exe and you use following command to begin the conversion:

    dmg2img -i  -o 
  • Finally you can burn the new *.img file with a simple right click in the Windows-Explorer.