The Network Master was considering the elementals of QoS with much joy.
The student approached and asked “Master, why is that that you do not permit the Storage traffic to burst to full speed ? Is it not the most important traffic on the network ?”
The Master looked at the Student woefully.
The Student was sure and burst out: “Is it not true that Storage traffic needs a lot of bandwidth and should get priority to ensure that servers run as fast as possible ?”.
“You must contemplate the oneness of the flow and be aware of the entirety of the requirement. Consider. Do not the disks spin to serve data to the servers to serve data to users ? It is the users that are most important, and the flow of data from users to the servers that generate the meaningful interaction of data. The amount of the user data is small but most important.” the Master said equably.
“Therefore, it is vital to ensure that user data is also protected is it not ?” the Master pointed out.
The Student struggled with this and said “But Master, if the Servers cannot reach their Disks, will they not crash ?”
And the Master smiled and said “This is, of course, true. But there is a big difference between high bandwidth and guaranteed packet delivery. It is not the size of the bandwidth that determines the outcome but the balanced sharing of the flow with all services”.
And the Student laughed, because he was enlightened.
Inspiration – PFC/ETS and storage traffic: the real story – Ivan Pepelnjak – Ioshints.info –
Other posts in the series
- Network ZEN: The Same Problem can Seem Different
- Network ZEN - Frames or Packet
- Network Zen - The Flow may only be seen when it is not present.
- Network Zen - Standardisation and Failure
- Network Zen - Standardisation
- Network ZEN - Storage traffic isn't so Important (This post)
- Network ZEN: A Switch
- Network ZEN: OSPF or EIGRP
- Network ZEN: Management or Monitoring
- Network ZEN: Stackable or Chassis Switches