RESEARCH
Peeking into Cloud for better Application
Manageability
Sambit Sahu
IBM Research
© 2009 IBM
Corporation
RESEARCH
Cloud Virtualizes Resources (cpu, mem, network, storage..)
 Cloud simplifies resource access through
virtualization
Service X
– User can get easy and inexpensive access to virtualized
resources
– Lower entry barrier with pay as you use
– On-demand elastic resource access
 Implication on application management hosted
on Cloud
– Decoupling between underlying resources and application
management layer
– May not even have ability or control over application
placements or deployments
– Typically Cloud provider and Service Provider or Users
belong to different organizations
 Challenges
– How to efficiently manage applications where
– No physical resource access or control due to virtualization
layer
– No or limited visibility on “what-is-going-on” in the physical
resource level
Service Y
Application
1
Application 2
Application Management Layer
Cloud Resource Provision Layer
Hypervisor Layer
Trusted
Virtual
Domains
server, network, storage, middleware resources
– What support or primitives need to be made available to
facilitate efficient problem resolution?
© 2009 IBM Corporation
RESEARCH
Analysis of Open Forum Message Threads of a Large Cloud
Provider
 Analyzed open forum message threads for problem classification and
resolution process understanding
– Collected messages posted on a Cloud open forum over last three years
– About 8000 unique message threads with about 38000 messages
– Analyzed messages over 3 months period and random sampling of messages over rest of
the period
– Major problem categories and classifications
– Nature of resolutions
 Objective
– Understand top problems and solutions provided by the cloud provider
– Understand impact of information hiding due to virtualization on problem resolution
– Determine if any information and/or tooling would help service providers and users for
efficient problem resolution/isolation
© 2009 IBM Corporation
RESEARCH
Common Symptoms and stage based problem
classification
Instance
Unreachabl
e
Instance
Unbootable
Provision
ing
Pending
Fig 1: Commonly Encountered Symptoms
•
•
•
•
Instance reachability problems
•
Virtualization mask failures
Connectivity issues
•
Infrastructure network problems, firewall rules,…
Component: Virtual infrastructure issues
•
•
Management of instance depends on instance
Instance unbootable
•
Fig 2: State based problem classification
Provisioning stage – least problems encountered
•
•
•
Most management & third party target this
Running stage – most problems encountered
Terminating stage – surprisingly second largest
contributor of problems
Unable to disconnect/connect virtual infrastructure
© 2009 IBM Corporation
RESEARCH
Some Problem Resolution Statistics
Figure 3: About 97 administrators responding to users via
open forum where few administrators answered
majority of the problems (20 admin accounted for
more than 80%)
Figure 4: Resolution Time
60% problems were resolved in a day Additional
20% problems took more than additional 3 days
© 2009 IBM Corporation
RESEARCH
Multiple problems manifest with same symptoms
Typical steps taken to resolve/fix the problems
•
Level of support and solutions for resolving problem
•
Instance Reboot
•
Host Reboot
•
Software Fixes
•
Manual modification of infrastructure state
•
Manual modification of network configuration
• Firewall
• Router configuration
Fig 3: Same symptoms for different set of problems
© 2009 IBM Corporation
RESEARCH
Summary
 Layering in a Cloud (virtualization of physical resources) hides
crucial information away from users
– Multiple problems manifest as same symptoms
 Issues
– What information can and should be shared between cloud provider and
cloud users or service providers?
– How to achieve this peeking without compromising security issues?
 Some initial thoughts on information unlayering
– Topology view
– Dependent resource health
– Resource logs
– Dependent access policies
-…
© 2009 IBM Corporation