Less known Solaris Features: Point-in-time copy with AVS - Part 7: Starting a point-in-time copy
Okay, before using the merits of point-in-time copies, we have to configure such copies. The configuration of this copies is done with the with the iiadm
command. In this part of the tutorial i will show you how to configure the different kinds of point-in-time copies.
Common prerequisite
At first we have to enable the Availability suite. This is independent from the method of doing the point-in-time copy. When you´ve used the AVS before, you don´t need this step
Please answer the last question with y
. By doing so, all the services of the AVS we need in the following tutorial are started (besides the remote replication service)
Create an independent copy
Now we can configure the point in time copy. This is really simple.
That´s all. What does this command mean: Create an independent copy of the data on the slice /dev/rdsk/c1d0s3 on /dev/rdsk/c1d1s3 and use /dev/rdsk/c1d1s3 for the bitmap. As soon as you execute this command, the copy process starts. We decided to use an independent copy, thus we start a full copy of the master volume to the shadow volume. As long this fully copy hasn´t completed, the point-in-time copy behaves like an dependent copy. Now we check the configuration.
The highlighted part is interessting. The bitmap is clean. This means, that there are no changes between the master and the shadow volume.
Create an independent copy
Creating an dependent copy is quite easy. You have just alter the command a little bit, you´ve used to create independent one.
Just subsititue the ind
with the dep
and you get a dependent copy.
Create an compact independent copy
How do you get a compact depedent copy? Well, there is no command to force the creation of such a copy. But it´s quite easy to get one. When the shadow volume is smaller than the master volume, the system chooses the compact independent copy automatically. We´ve created two small slices, when we formated the harddrive. One of the small slices is /dev/rdsk/c1d1s6
. Let´s use it as the shadow volume. This volume has only a size 32 MB while the master volume is 256 lMB large.At first we create an dependent copy again, but with different volumes:
Now let´s check the status of the point-in-time copy configuration:
Et volia, you´ve configured a compact depedent copy.