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Configuring the Syslog Service on VMware

Posted in Virtual - VMWare (30),Visio Samples - Stencils (457) by Guest on the July 30th, 2017
All ESX and ESXi hosts run a syslog service (syslogd), which logs messages from the VMkernel and other system components to a file.
To configure syslog for an ESX host:
Neither vSphere Client nor vicfg-syslog can be used to configure syslog behavior for an ESX host. To configure syslog for an ESX host, you must edit the /etc/syslog.conf file. 
To configure syslog for an ESXi host:
On ESXi hosts, you can use the vSphere Client or the vSphere CLI command vicfg-syslog to configure the following options:
  • Log file path: Specifies a datastore path to the file syslogd logs all messages.
  • Remote host: Specifies a remote host to which syslog messages are forwarded. In order to receive the forwarded syslog messages, your remote host must have a syslog service installed.
  • Remote port: Specifies the port used by the remote host to receive syslog messages.
To configure syslog using vSphere CLI command:
For more information on vicfg-syslog, refer the vSphere Command-Line Interface Installation and Reference Guide.
To configure syslog using vSphere Client:
  1. In the vSphere Client inventory, click on the host.
  2. Click the Configuration tab.
  3. Click Advanced Settings under Software.
  4. Select Syslog in the tree control.
  5. In the Syslog.Local.DatastorePath text box, enter the datastore path to the file where syslog will log messages. If no path is specified, the default path is /var/log/messages.
The datastore path format is [<datastorename>] </path/to/file> where the path is relative to the root of the volume backing the datastore.
Example: The datastore path [storage1] var/log/messages maps to the path / vmfs/volumes/storage1/var/log/messages.
  1. In the Syslog.Remote.Hostname text box, enter the name of the remote host where syslog data will be forwarded. If no value is specified, no data is forwarded.
  2. In the Syslog.Remote.Port text box, enter the port on the remote host where syslog data will be forwarded. By default Syslog.Remote.Port is set to 514, the default UDP port used by syslog. Changes to Syslog.Remote.Port only take effect if Syslog.Remote.Hostname is configured.
  3. Click OK.
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Six common Cloud Services Requirements

Posted in Virtual - VMWare (30),Visio Samples - Stencils (457) by Administrator on the July 17th, 2017
  1. Wide-area networking
  2. Intra-cloud network
  3. Compute cluster (Virtual instance) – (Elastic)
  4.  Storage service (Blob, Table and Queue)
  5.  Disaster Recovery / Business Continuity
  6.  Security (design, build, deployment, management / maintenance)
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Challenges in Cloud Computing from the Industry (Providers)

Posted in Virtual - VMWare (30),Visio Samples - Stencils (457) by Guest on the July 15th, 2017

Encompass computation, storage, and networking and security

Replacement Cost

  • Exponential increase in cost to maintain the infrastructure
  • Vendor Lock-in

 

No standard API or protocol can be very serious

  • Standardization

 

No standard metric for QoS is limiting the popularity

  • Security and Confidentiality

 

No standard metric for QoS is limiting the popularity

 

Trust model for cloud computing

  • Control Mechanism
  • Users do not have any control over infrastructures

 

Concerns from Research Community

  • Conflict to legacy programs
    • With difficulty in developing a new application due to lack of control
  • Provenance
    • How to reproduce results in different infrastructures
  • Reduction in Latency
  • No specially designed interconnect used
    • Very low controllability in layout of interconnect due to abstraction
  • Programming Model
    • Hard to debug where programming naturally error-prone
    • Details about infrastructure are hidden
  • QoS Measurement
    • Especially for ubiquitous computing where context changes

 

Comparing compute clusters

  • Instance performance
    • Java-based benchmarks
  • Cost-effectiveness
    • Cost per benchmark
  • Scaling performance
    • Why is it important?
    • Scaling latency

Comparing storage services

  • Cover blob, table, and queue storage services
  • Compare “read” and “write” operations
    • Additional “query” operation for table
  • Metrics
    • Operation latency
    • Cost per operation
    • Time to consistency
  • Network latency to the closest data center

 

Storage performance

  • Operation response time has high variation
  • Storage performance depends on operation type

 

Three metrics

    • Benchmark finishing time
    • Monetary cost per benchmark
    • Scaling latency

 

End-to-end metrics

  • Simple
  • Has predictive value
  • Abstracts away the implementation details
    • Different design trade-offs
    • No single one stands out
    • Cloud performance can vary significantly
      • 30% more expensive -> twice as fast
      • Storage performance can differ in magnitudes
      • One cloud’s intra-data center bandwidth can be 3X higher than the other

 

Security and Confidentiality (abstraction of the underlying infrastructure)

  • Multi-tenancy (shared environments, may or may not have access to software)
    • Economical because software development and maintenance costs are shared. It can be contrasted with single-tenancy, an architecture in which each customer has their own software instance and may be given access to code
  • Single-tenancy (an architecture in which each customer has their own software)
    • The provider has to touch multiple instances of the software in order to make updates.
  • Security and Confidentiality
  • IT Audit Risk is largely driven by:
      • Deployment Model
      • Service Model

     

  • Nature of Applications & Data in Cloud
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