I hope you can give me some helping experiences.
A short Introduction of myself and the association I am working for.
This system is based on the Oracle Collaboration Suite and not supported anymore. The system is needed to secure that the recipient got the mail. I Knoow w'ell have to develop a special protocol for that. The architecture will be closed that means onyle mailboxes within our adressbook can communicate with each other.
That is the reason why we have to migrate nearly 100K mailboxes to a new system.
We have to decide until end of September between 3 System:
One of that is Zimbra.
I have to say that i have a lot of concers to migrate to an open source system. We thought about using the community version because we have to add a lot of funktionality to our groupware installation and we only have very low budget because our customers are not-for-profit sport clubs.
My questions to you..
Do you think that we can run a high available instance of Zimbra with 60K-200K mailboxes?
Which experiences have you made with administrating Zimbra?
How many days have we to calculate only for administrating a system like that?
How secure is it running Zimbra? Are eploits rapidly fixed by the comminty?
Sorry for my horrible English and thank you for your answers...