Just use samba4 (cldap) replication/dns mode between 2 hosts. -------- Original-Nachricht -------- > Datum: Tue, 30 Oct 2012 10:04:48 -0400 > Von: Carlin Hefner <carlinohef...@gmail.com> > An: users@sogo.nu > Betreff: Re: [SOGo] Backup Redundant System
> Thank you Nathanael, > Your solution actually looks the best, because I started discovering > issues > with trying to use DRBD over WAN. > I've started looking into your solution and have a couple questions. BTW I > apologize, I'm a bit new at this, so I could be overlooking the obvious. > > I have the MX and DNS failover under control for access to either > location, > and the replication sounds great, but how can I get service failover for > LDAP, SQL etc if the primary network or server goes down? Eg if the > primary > server goes down, the MX failover will send messages to the backup MX but > then that backup MX is still pointing to the primary LDAP db. I could use > a > failover to point it to the replicated LDAP but that wouldn't work since > it's a consumer, not a provider, right? Same with the SQL DB? > > Thanks > Carlin > > > On Tue, Oct 30, 2012 at 6:05 AM, Nathanael Bettridge > <nbettri...@yahoo.com>wrote: > > > ** > > I know there's been active/passive disk image designs mentioned, but for > > something more application-level (and more expansive): > > > > - Use LDAP with replication for accounts > > - Use Cyrus IMAPd native replication and frontend/backend to handle mail > > (you can combine this with a Cyrus Murder to have a primary DB at each > site > > along with a replica DB of the alternate site) > > - Use native SQL replication for the SOGo database > > - Use MX failover for inbound email, with live MXes at each site > pointing > > at the same LDAP db and handing off delivery to the Cyrus frontends > > - Use anycast addresses, or DNS failover scripting, for > user-connectivity > > failover (for some clients we can use SRV record tricks too) > > > > We use a setup something like this and it works rather well, though > > requires a fair few VM instances to run. We also put simple > (non-persistent > > disk) loadbalancing/failover VM's in front of each service that can > handle > > automatic failover (SQL, LDAP read, MX and Cyrus Frontends for example) > to > > handle failures automatically. > > > > It also makes backup easy since you run backup on the replicas and > nobody > > notices :) > > > > However, we're not using this with Exchange emulation (yet) so it'll be > > interesting to figure out how it behaves in this environment > > > > However for a simple deployment DRBD is probably easier :) > > > > Thanks, > > -Nathanael Bettridge > > > > > > carlinohef...@gmail.com wrote: > > > > Hi, > > I'm am looking at venturing into sogo as an exchange replacement, and > have a > > question before I begin. I promise I have searched before posting, but > can't > > find anything related (or I may have poor keyword choices :-) So I > apologize if > > this has been discussed already. > > > > We have a couple of office locations, and I'd like to set up 2 servers, > 1 at > > each location, that mirror each other. That way if one location goes > down > > (power or internet loss or hardware failure) the other server can still > at > > least receive SMTP. It would be great if the client side connectivity > could > > also work when one or the other servers go down, but not as important as > making > > sure we don't miss any incoming mail over SMTP. > > > > Is this possible? > > > > Thanks in advance, > > Carlin > > > > > -- > users@sogo.nu > https://inverse.ca/sogo/lists -- users@sogo.nu https://inverse.ca/sogo/lists
