Field Notes
The Infrastructure That Starts the Infrastructure - DNS, identity, time and management services should not become circular dependencies during recovery.
Categories:
[Field Notes],
[Infrastructure]
Modern infrastructure has become very good at consolidation.
Virtualization allows us to move services away from dedicated hardware. Central identity removes local accounts. DNS becomes authoritative and dynamic. Configuration management keeps systems consistent. Monitoring provides a common opera...
High Availability Is More Than a Running VM
Categories:
[Field Notes],
[Infrastructure]
A virtual machine can recover successfully while the service it belongs to remains unavailable. The difference matters more than it first appears.
High availability is one of those terms that sounds precise until several different parts of an infrastructure start using it at the same time.
A vir...
A Direct Link Is Not a Network - Point-to-point 25, 40 or 100 GbE can be excellent for migration, replication and storage traffic, but only if we treat it as a deliberate failure domain rather than a shortcut.
Categories:
[Field Notes],
[Infrastructure]
There is something very attractive about connecting two virtualization hosts directly with a pair of high-speed network interfaces.
No switch. No spanning tree. No intermediate fabric. No uplink contention. Just a cable between two machines and a large amount of bandwidth available for migration,...