IsvaraIsvara
Tools
Define good

The SLA Builder.

Until you've defined good, every complaint is a crisis. Set your service classes and the four indicators, and take away the agreement itself: one shared benchmark, tiers that differ by price and nines, and a document your tenants can hold you to.

Service classes

The guide's model: same threshold for every class ('2.5% will serve all classes - you just need to adjust the nines'); classes differ by price, overcommit and the promised percentage of time.

Goldpricex · CPU
availability= 10.8 min/monthperformance
Silverpricex · CPU
availability= 21.6 min/monthperformance
Bronzepricex · CPU
availability= 43.2 min/monthperformance

Failure windows are deliberately spaced: Silver tolerates roughly twice Gold's window because it costs half as much. The guide explicitly rejects different thresholds per class - Silver could end up performing better than Gold, and the gaps are hard to explain.

The four indicators

One benchmark to rule them all: every class is measured against the same four thresholds, per VM, as 5-minute averages.

The agreement

Live preview. Copy it as Markdown and take it to the meeting.

Service Level Agreement
Private Cloud · IaaS
1 · Service classes
ClassPriceCPUAvailabilityPerformance
Gold1.00x1:199.975%99.9%
Silver0.50x1:299.95%99.8%
Bronze0.25x1:499.9%99.6%
2 · Performance (slow time)

Every VM is scored each 5 minutes against cpu ready2.5%, memory contention1%, disk latency10ms and network transmit dropped packets0%. The monthly figure is the percentage of intervals each VM passes. Crossing any one indicator fails the interval; failure is binary.

3 · Availability (downtime)

Measured per VM by Guest OS response; a running but isolated VM fails. Gold 99.975% (10.8 min/month), Silver 99.95% (21.6 min/month) and Bronze 99.9% (43.2 min/month). Customer-initiated reboots, guest-caused downtime and in-window maintenance are excluded. Performance has no maintenance window: there is no scheduled slow time.

4 · Compliance and remedy

Compliance: 99.95% for every class - securing everyone is in the provider's interest. A breached month is remedied as a credit on the next billing cycle.