📘 02-04: Change Management & Agreements¶
📌 Change Management¶
Change management is the process of proposing, reviewing, approving, implementing, and documenting changes to minimize risk of outages.
🔹 A change request typically includes¶
- Reason and scope of the change
- Risk assessment and potential effects
- Implementation plan (steps, timing, maintenance window)
- Rollback (back-out) plan — how to revert to the last known-good state
- Approval/sign-off from a change advisory board or manager
A change without a rollback plan is a gamble. Always know how to undo it.
📌 Common Agreements & Policies¶
| Term | Meaning |
|---|---|
| SLA (Service Level Agreement) | Agreed service levels — uptime %, response/repair times, penalties |
| AUP (Acceptable Use Policy) | Rules for how users may use network resources |
| MOU (Memorandum of Understanding) | Informal agreement of intent between parties |
| SOW (Statement of Work) | Detailed deliverables/scope for a project or vendor |
| NDA (Non-Disclosure Agreement) | Protects confidential information |
📌 Reliability Metrics¶
| Metric | Meaning |
|---|---|
| MTBF (Mean Time Between Failures) | Average operating time before a device fails |
| MTTR (Mean Time To Repair) | Average time to restore a failed device/service |
📌 Fire & Cable Safety Ratings¶
| Rating | Where used |
|---|---|
| Plenum (CMP) | Air-handling spaces (HVAC plenums) — fire-resistant, less toxic smoke |
| Riser (CMR) | Vertical shafts between floors |
Tip
Key idea — Every change should be documented, reviewed, approved, and reversible (rollback plan). Know the common agreements (SLA, AUP) and reliability metrics (MTBF, MTTR).
See also: Network Documentation, Fault Tolerance & Recovery
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