Challenges of Self-Managing Systems: a System Administrators - - PowerPoint PPT Presentation

Challenges of Self-Managing Systems: a System Administrator’s Perspective

• Dr. Alva L. Couch, Associate Professor
• f Computer Science,

Tufts University, Medford, MA USA couch@cs.tufts.edu

Sysadmins and self-managing systems

• Self-managing systems: built from bottom

up, system-centric

– How to make systems more robust

• System administration: built from the top

down, administrator (people) centric

– How to empower people to do their jobs

Sysadmin Challenges for Self-managing Systems

• Personal liability: it is not the self-healing system

that can lose its job

• Semantic distance and the problem of common

referents: system administrators do not understand what self-healing systems do

• Expense of policy changes: small changes can

incur large (political) costs

• Interference with auditing: can’t both “fix it” and

“analyze it”

Desirable Forms of Self-Management

• Strong closures: “keep the box closed!”

– “Half-open” is worse than “open” – We don’t want to debug “your” code (or “tweak your knobs”!)

• Guarantees: “what can we expect?”

– SLA for administrators – Controls concentrate on SLA parameters:

• ptimization/intrusiveness tradeoffs

“Like Hardware”

• No need to build system
• Automatic baselining and upgrades
• Directly modify only configuration
• Configuration concentrates on SLA
• Replacement if fails
• Remote diagnosis

Low-Hanging Fruit

• Closed, optimized network services

– File sharing – Web services

• Don’t forget management aids

– Distributed

• backup and recovery
• email and spam control
• firewalling and virus control

– Tiered (local/remote) filesystems – User authentication and authorization

The Near Future

• Commoditization of services: file service

becomes like routing; a reliable closed

• box. Already almost true.
• Gradual commoditization of higher-level

“policy-free” services, e.g., user privilege management.

• System administrator’s job becomes

component engineering.

What Won’t Happen

• Peer-peer adoption without strong

convergence and fault-tolerance guarantees (peer-peer is a “problem”, not a “solution”)

• Commoditization of administrator interface

and business policies: “variant taxonomies

• f policy”

Standards

• Existing standards

– Will aid developers; should not concern administrators – About how a tool should interact, not about how an administrator should interact

• Standards that have helped sysadmins:

– pop, imap, smtp, … – Sysadmin controls service; user controls choice of client/GUI

• Some potentially helpful standards

– Semantics of SLA parameters for component solutions – Base (“policy-free?”) semantics for user bindings including authentication and authorization.

Conclusions

• Build self-managing components.
• Provide an interface with strong

semantics.

• Let sysadmins do the rest:

– User interface – Translation from business policy to system policy.