device-eth0-does-not-seem-to-be-present,delaying initialization

Error:  "device-eth0-does-not-seem-to-be-present"

when I cloned one of my Linux virtual machine. So the cloned machine was not able to detect the NIC and every time I tried to restart the network it was throwing this error


The MAC id details for the NIC card is stored in the below mentioned file which is automatically created every time the machine boots.


If you open this file the contents would be like this

Delete this file

           rm -f /etc/udev/rules.d/70-persistent-net.rules

Reboot the machine i.e  init 6

Now we can see difference in MAC id and NIC card name

Copy the new MAC id and NIC card name to your ifcfg-eth0 file

vi /etc/sysconfig/network-scripts/ifcfg-eth0

Restart the Network service using :  service network restart

check for IP details using " ifconfig"

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 Swift Components:

 1.Proxy Server
Tie together the Swift architecture
Request routing
Exposes the public API

Maps names to entities (accounts, containers, objects) on disk.
Stores data based on zones, devices, partitions, and replicas
Weights can be used to balance the distribution of partitions
Used by the Proxy Server for many background processes
 3.Object Server
Blob storage server
metadata kept in xattrs
data in binary format
Object location based on name & timestamp hash

Swift & Large Object Storage:

Default 5GB limit on the size of an uploaded object
Segmentation makes download size of a single object is virtually unlimited
Segments large object are uploaded and a special manifest file is created when downloaded, all segments are concatenated as a single object.
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Possible parallel uploads of segments.

Swift Components:

       Keep the system consistent, handle failures

       Process failed or queued updates

      Verify integrity of objects, containers, and accounts

Container Server:
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Account Server:
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Search is limited to queries based on the object's name and to a single bucket. No metadata or content-based search capabilities are provided.