How to choose the best hardware for you cache server

Your current needs and your midterm objectives ?

First of all, you must identify your current situation:
  • What is the current traffic in term of bandwidth with users ?
  • How many end users are you currently having ?
  • How long do you want to keep objects available in cache ?
Then you need to think about evolution of your needs in the future:
  • What shall be your bandwidth needs in the next 3 years from now?
  • How many end-users you will need to support in 3 years ?

What type of hardware to choose ?

Once you how identify to your needs, you can think of the type of hardware to select...
Size of Hard Disks:
  • Since the version 3.x, VCB (Video CacheBox) supports multi-disks servers with a maximum of 10 hard disks maxi as cache disk space.
  • Having a heavy traffic (>100Mbps) means a minimum of 3TB disk space for your cache
  • Keeping objects in cache for a long duration means a need for big cache disk space (3TB mini)
  • Caching big objects size (Windowsupdate, Games ISO, etc...) requires big cache disk space (3TB mini)
Memory Size:
  • The server uses mainly hard disks to cache but also its RAM memory for most popular objects
  • Memory size depends on the number of cores processor; 4GB of RAM per core is recommended
Type of Processor:
  • With a built-in Optimization Engine for Internet traffic improvements, VCB Server requires powerful processors
  • With traffic up to 100Mbps, Intel i3 is recommended
  • With traffic up to 300Mbps, Intel i5 mini is needed
  • With traffic up to 1Gbps, Intel i7 mini is mandatory
  • Over 1Gbps traffic, Intel Xeon is strongly recommended
  • In any cases, choose powerful processor with proper architecture.
Network Interface Cards:
  • VCB is now able to manage 2 NICs for mode Gateway (ETH1 as LAN and ETH0 as WAN)
  • With Mikrotik, you only need 1 NIC for Transparent Proxy
  • With Cisco, you need 1 NIC only with Layer2 mode or GRE
  • Consider using a 10Gbps NIC if your traffic is above 1Gbps
Examples of Hardwares you can use as models...

How to organize Hard Disks structure ?

If you go with Multi-Disks architecture you must pay attention to the following possible scenarios.
Scenario 1: 1 Hard Disk configured as Boot/OS disk and additional disks for Cache Space - Recommended configuration
  • Disk used as Boot/OS does not need to be very big, 256GB mini is good enough.
  • In such Scenario SSD disk can be used only as server Boot/OS disk
  • Example of Disks architecture: 256GB SSD as Boot/OS and WD NAS Hard Drives as Cache Disks
Scenario 2: 1 Hard Disk configured as Boot/OS/Cache and additional Disks for Cache Space
  • Here, all disks are used for caching, including the Boot/OS disk.
  • Boot/OS disk will work much more as it will have to manage Operating System and logs
  • Never consider using an SSD disk as Cache disk as its lifetime will be significantly reduced because caching is highly I/O demanding

Disk Size vs. Max Size Object

Max Size Object parameter depends on the size of hard drive (cache) and tells the server if an object as to be saved in cache or not. Objects bigger than the Max Size Object parameter will not be saved.
Disk Size (GB) 2505001,0002,0003,0004,0006,000
Max Size Object (MB) 3987911,6213,1868,1928,1928,192
Only valid for YouTube, Instagram, Apple apps, etc...
Valid for Apple iOS, HD movies, etc...
Required for WindpowsUpdate

Examples of Hardware Configurations

Traffic 50Mbps and 700 end users:
  • Disk as Boot/OS: 1x512GB SSD
  • Disk: 1x4TB SATA 5000 RPM
  • RAM: 64GB memory
  • Processor: Intel i5
  • NIC: 1Gbps
Traffic 600Mbps and 5,000 end users:
  • Disk as Boot/OS: 1x512GB SSD
  • Disks as Cache: 4x4TB SATA 7200 RPM
  • RAM: 256GB memory
  • Processor: Dual Xeon
  • NIC: 1Gbps