By using this site, you agree to our updated Privacy Policy and our Terms of Use. Manage your Cookies Settings.
446,231 Members | 1,605 Online
Bytes IT Community
+ Ask a Question
Need help? Post your question and get tips & solutions from a community of 446,231 IT Pros & Developers. It's quick & easy.

replication question

P: n/a
ken
Hi,
I set up replication with a Frontend/Backend database set up. I noticed
that when I sync the master with the replica in the same folder where I
set up the replication, everything works fine and when I test for
conflicts I get what I expect. However if I change the folder to say
Copy of Folder when I sync the master automatically wins all conflicts
without asking me, for all tables except 1. I find this very unusual.
Are there limitations to where I can store master/replica databases?

Thanks

Dec 6 '06 #1
Share this Question
Share on Google+
5 Replies


P: n/a
"ken" <ge****@gmail.comwrote in
news:11**********************@79g2000cws.googlegro ups.com:
I set up replication with a Frontend/Backend database set up. I
noticed that when I sync the master with the replica in the same
folder where I set up the replication, everything works fine and
when I test for conflicts I get what I expect. However if I change
the folder to say Copy of Folder when I sync the master
automatically wins all conflicts without asking me, for all tables
except 1. I find this very unusual. Are there limitations to where
I can store master/replica databases?
Well, I don't know what you mean by "change the folder to say Copy
of Folder" but if you're changing the folder name, then you've just
created a "dead replica." Here's a lengthy explanation of what a
"dead replica" is (all on one line):

http://groups.google.com/group/comp..../msg/9f5a84194
fa6c653

One replica can win all conflicts if it has a higher replica
priority. A Design Master has a priority of 100. Every replica has a
priority 90% of its parent replica, so replicas created directly
from the DM have a priority of 90, replicas created from one of
those replicas would have a priority of 81. In resolving conflicts,
all other things being equal, the replica with the higher priority
wins.

I don't like this kind of automatic conflict resolution myself, so
the way to insure that it doesn't happen is to make sure that all
the replicas being edited have exactly the same priority. I believe
the priority can be changed after creation of the replica, but I'm
not certain about that. Hmm, no, I guess you can't (JRO provides the
property but says it's read-only).

Copying or renaming a replica does *not* change its priority.

Another point: you should *never* use the Design Master of your
replica set for regular editing. It is important that you put it in
a safe place and synch with it only often enough to keep it from
expiring (the default retention period is 1000 days), but you
shouldn't use it for anything except making schema changes. If you
create a new replica as your production editing replica, it will
have the same replica priority as your other replicas, so your
problem ought to be solved.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/
Dec 6 '06 #2

P: n/a
ken
Hi,
Thanks for the reply.
Here is what I did...I have a design master and a replica in a folder
called "Folder" I entered data so that there would be conflicts in
certain tables. Then I did a Ctrl-C Ctrl-V on the folder containing the
databases. Thus I got "Copy of Folder". That's what windows does when
it makes a copy of something and the user wants to put it in the same
place as what is being copied. Finally my result was when I Sync in
the "Copy of Folder" folder Access does not generate all the conflict
tables and thus I can't see all of the conflicts that I expected to
see. However when I sync in the original "Folder" folder, where I
entered the data and created teh replica from the Design master,
everything is ok. I get all my conflicts.

That's what puzzles me.

Regarding the design master...I didn't know you shouldn't enter data
into it....? Now that I know rather having the Design Master and
Replica setup...I might have Design Master(100) Replica1(90) and
Replica2(80). I need one of the used database replicas to have a higher
priority number. The current policy is that Replica1 should always win
conflicts.

Thanks
David W. Fenton wrote:
"ken" <ge****@gmail.comwrote in
news:11**********************@79g2000cws.googlegro ups.com:
I set up replication with a Frontend/Backend database set up. I
noticed that when I sync the master with the replica in the same
folder where I set up the replication, everything works fine and
when I test for conflicts I get what I expect. However if I change
the folder to say Copy of Folder when I sync the master
automatically wins all conflicts without asking me, for all tables
except 1. I find this very unusual. Are there limitations to where
I can store master/replica databases?

Well, I don't know what you mean by "change the folder to say Copy
of Folder" but if you're changing the folder name, then you've just
created a "dead replica." Here's a lengthy explanation of what a
"dead replica" is (all on one line):

http://groups.google.com/group/comp..../msg/9f5a84194
fa6c653

One replica can win all conflicts if it has a higher replica
priority. A Design Master has a priority of 100. Every replica has a
priority 90% of its parent replica, so replicas created directly
from the DM have a priority of 90, replicas created from one of
those replicas would have a priority of 81. In resolving conflicts,
all other things being equal, the replica with the higher priority
wins.

I don't like this kind of automatic conflict resolution myself, so
the way to insure that it doesn't happen is to make sure that all
the replicas being edited have exactly the same priority. I believe
the priority can be changed after creation of the replica, but I'm
not certain about that. Hmm, no, I guess you can't (JRO provides the
property but says it's read-only).

Copying or renaming a replica does *not* change its priority.

Another point: you should *never* use the Design Master of your
replica set for regular editing. It is important that you put it in
a safe place and synch with it only often enough to keep it from
expiring (the default retention period is 1000 days), but you
shouldn't use it for anything except making schema changes. If you
create a new replica as your production editing replica, it will
have the same replica priority as your other replicas, so your
problem ought to be solved.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/
Dec 7 '06 #3

P: n/a
ken
David,
I read your link you sent me...
Things make a little more sense now. I need to have a design master,
and 2 replicas. Replica1 will have a higher priority then Replica2.
Replica1 will be on the local server. Replica2 will be on a remote
server. You mentioned that the Master needs to be synced only once a
month. My question is could Replica1 and Replica2 be synched more then
once a month? I need for them to be updated at least once a
week....very rarely more often then that? Then once a month I can
resync the master with the replicas...

What is Jet Synchronizer and where do I get it?

Thanks
ken wrote:
Hi,
Thanks for the reply.
Here is what I did...I have a design master and a replica in a folder
called "Folder" I entered data so that there would be conflicts in
certain tables. Then I did a Ctrl-C Ctrl-V on the folder containing the
databases. Thus I got "Copy of Folder". That's what windows does when
it makes a copy of something and the user wants to put it in the same
place as what is being copied. Finally my result was when I Sync in
the "Copy of Folder" folder Access does not generate all the conflict
tables and thus I can't see all of the conflicts that I expected to
see. However when I sync in the original "Folder" folder, where I
entered the data and created teh replica from the Design master,
everything is ok. I get all my conflicts.

That's what puzzles me.

Regarding the design master...I didn't know you shouldn't enter data
into it....? Now that I know rather having the Design Master and
Replica setup...I might have Design Master(100) Replica1(90) and
Replica2(80). I need one of the used database replicas to have a higher
priority number. The current policy is that Replica1 should always win
conflicts.

Thanks
David W. Fenton wrote:
"ken" <ge****@gmail.comwrote in
news:11**********************@79g2000cws.googlegro ups.com:
I set up replication with a Frontend/Backend database set up. I
noticed that when I sync the master with the replica in the same
folder where I set up the replication, everything works fine and
when I test for conflicts I get what I expect. However if I change
the folder to say Copy of Folder when I sync the master
automatically wins all conflicts without asking me, for all tables
except 1. I find this very unusual. Are there limitations to where
I can store master/replica databases?
Well, I don't know what you mean by "change the folder to say Copy
of Folder" but if you're changing the folder name, then you've just
created a "dead replica." Here's a lengthy explanation of what a
"dead replica" is (all on one line):

http://groups.google.com/group/comp..../msg/9f5a84194
fa6c653

One replica can win all conflicts if it has a higher replica
priority. A Design Master has a priority of 100. Every replica has a
priority 90% of its parent replica, so replicas created directly
from the DM have a priority of 90, replicas created from one of
those replicas would have a priority of 81. In resolving conflicts,
all other things being equal, the replica with the higher priority
wins.

I don't like this kind of automatic conflict resolution myself, so
the way to insure that it doesn't happen is to make sure that all
the replicas being edited have exactly the same priority. I believe
the priority can be changed after creation of the replica, but I'm
not certain about that. Hmm, no, I guess you can't (JRO provides the
property but says it's read-only).

Copying or renaming a replica does *not* change its priority.

Another point: you should *never* use the Design Master of your
replica set for regular editing. It is important that you put it in
a safe place and synch with it only often enough to keep it from
expiring (the default retention period is 1000 days), but you
shouldn't use it for anything except making schema changes. If you
create a new replica as your production editing replica, it will
have the same replica priority as your other replicas, so your
problem ought to be solved.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/
Dec 7 '06 #4

P: n/a
"ken" <gg****@gmail.comwrote in
news:11*********************@j44g2000cwa.googlegro ups.com:
Here is what I did...I have a design master and a replica in a
folder called "Folder" I entered data so that there would be
conflicts in certain tables. Then I did a Ctrl-C Ctrl-V on the
folder containing the databases. Thus I got "Copy of Folder".
That's what windows does when it makes a copy of something and the
user wants to put it in the same place as what is being copied.
Finally my result was when I Sync in the "Copy of Folder" folder
Access does not generate all the conflict tables and thus I can't
see all of the conflicts that I expected to see. However when I
sync in the original "Folder" folder, where I entered the data and
created teh replica from the Design master, everything is ok. I
get all my conflicts.

That's what puzzles me.
What, exactly, are you trying to test? When you do that, you end up
with two entirely new ReplicaIDs, and the conflicts are no longer
reported, because you're no longer synching the two replicas that
the conflict data was entered in.

If you created your copy first, then edited to create the conflict,
then synched, you'd see behavior identical to the original replicas.

But I don't quite understand why you're doing this, as it's not a
test that has anything at all to do with the way any actual
replication topology should be set up or actually used.
Regarding the design master...I didn't know you shouldn't enter
data into it....? Now that I know rather having the Design Master
and Replica setup...I might have Design Master(100) Replica1(90)
and Replica2(80). I need one of the used database replicas to have
a higher priority number. The current policy is that Replica1
should always win conflicts.
That should work, then. However, you still have to understand that
when a conflict is reported, it has already been resolved -- all the
conflict report is telling is "hey! I resolved a conflict, but you
may want to check that I did it correctly!" When you run the
built-in conflict resolver, all you're doing is confirming that Jet
resolved the conflicts correctly. You could programmatically examine
the conflict tables and make the same determination, and delete the
conflict records that were correctly resolved. That would leave the
ones that were resolved wrong, and then you could have someone
examine those to see why the replica with higher priority did not
win (it would probably have to be a case of multiple updates, I
think -- it's theoretically possible, but oughtn't be common).

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/
Dec 7 '06 #5

P: n/a
"ken" <gg****@gmail.comwrote in
news:11**********************@j44g2000cwa.googlegr oups.com:
Things make a little more sense now. I need to have a design
master, and 2 replicas. Replica1 will have a higher priority then
Replica2. Replica1 will be on the local server. Replica2 will be
on a remote server. You mentioned that the Master needs to be
synced only once a month.
Er, well, the DM needs to be synched often enough that it doesn't
expire. I use once a month as a time period that is well within the
default retention period of 1000 days, but you could do it less
often and not have problems, as long as you do it more often than
once every 3 years or so.
My question is could Replica1 and Replica2 be synched more then
once a month? I need for them to be updated at least once a
week....very rarely more often then that? Then once a month I can
resync the master with the replicas...
You synch between your replicas as often as you need. That might be
once a month, once a week or once every hour.
What is Jet Synchronizer and where do I get it?
First off, you need to read all the Jet replication documents. A
list of all of them can be found under "Resources for learning about
Jet Replication" at:

http://www.dfenton.com/DFA/Replicati....php/Main_Page

The MS documentation assumes you're going to have the Office
Development toolkit (whichever one is appropriate for your version
of Access) and that you'll be using Replication Manager. But the
2003 version of the development tools (Visual Studio) stupidly
doesn't include Replication Manager and the Jet synchronizer. I
explain how to get the Jet synchronizer and how to set it up in this
post (all on one line):

http://groups.google.com/group/micro...replication/ms
g/3b7167c1462b2d2f

Indirect replication is complicated to learn and set up, but is
extremely efficient and safe once you have it working.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/
Dec 7 '06 #6

This discussion thread is closed

Replies have been disabled for this discussion.