I have a database by now lying on 1 server. A designer of another application written in XML on a different server wants to take on data from my database. He says he needs a replica of my database on his server to run his agent(s).
I’m a little cynical about it, because I do not understand why a simple lookup is not OK.
My question is:
What do I have to pay attention to regarding this replica?
Where could be disadvantages for my database, e.g. in performance…?
FYI: the data to take on (names and numbers)is not changing every minute and it is only 1 view.
Thank you for your help in advance
Leini
Subject: Replica on second server: What do I have to pay attention to
Leini,
If there is no issue with the other party seeing the database and contents then there should not be much of a problem. Essentially you want to ensure that they cannot change your data and that they do the majority of the work. I’d probably do the following:
If it causes no internal issues set the database to maintain a consistent ACL
Create a group entry in the ACL for the other party, type = Unspecified and give it reader access with no other attributes
Create that group in your Directory and put their server in it
If not already done so Create Cross certificates at the server-to-server level and grant access
Allow them to pull a replica across (Assumes they can do so locally at the server, i.e. Windows platform)
Agree a replication schedule, which they set up as a Pull Only from their end.
There are many other ways to do it but hopefully that gives you an idea.
Regards,
John
Subject: OK, that’s a good start.
Thank you for your help.I will discuss it a littel more in detail with the designer of the other application and if something sounds strange to me, I 'll come back to you more specific.
So far I feel well prepared for a first discussion.
Leini
Subject: Replica on second server: What do I have to pay attention to
I don’t know how much I can help, but I’ll tell you what I do know.
When you create a replica on another server, its very similar to creating an offline replica of a database, such as a notebook user’s mailfile. The database will exist on both servers, be accessible on both servers, and replicate on a schedule the same as a local replica. This is usally done where there are seperate sites with a WAN Link between them, so that users at both sites can access the database over a LAN connection without clogging up the WAN link to the other server.
In terms of performance, your database will be pretty much unaffected. Your designer will work on his replica, you and your users will work on your replica, and occasionally the two servers will replicate changes to one another. It is possible that for brief periods the databases will be different, as changes made on one will only transfer to the other during the server-server replication, but in my experience this is very rarely a problem, and as you point out, this is not a constantly-changing database.
I hope this sheds some light, I may be able to tell you more if you’re more specific.
Subject: RE: Replica on second server: What do I have to pay attention to
Thank you Christopher,for it looks like there is an advantage setting up the replica, because the traffic will not all go on 1 server but on 2 now.
But can I control that the replication settings on the replica are set to receive only?
What about the ACL? Need I to give manager access to the designer of the other application?
I know I can set the consistent ACL tick, but do I have the control over, who is added to the ACL? I don’t want to have other managers in my database.
I need to be sure that nothing unexpected happens to my database. I have more than 100 users per day - you can imagine the temperature of my phone ;-), if it doesn’t work for a day.
Thank you for your help,
Leini
Subject: RE: Replica on second server: What do I have to pay attention to
Leini
I’m not sure I fully understand - if you wish to divide the traffic between the two servers, then one-way replication may cause problems, as the users accessing the remote replica can make changes which will then not be replicated back to the main database. However, if changes are only ever made on the first replica, then one-way replication is OK, and will safeguard you from any mishaps in the XML application.
Regarding the ACL, there should be no need to give the designer Manager access. Find out exactly what he needs to be able to do (create agents, edit forms, read/write documents etc.) and just give the access required. You may find that as he is working with an external applicatin which just pulls data from the database, that he only needs Reader access to do it.