10-19-2009 09:03 AM
Hi,
We've got 4 Ironports C600 and we use DNS Round Robin on MX.
It works fine when all of the Ironport are working but I'm not sure about how it will work if one of them fails or if I put one of them in maintenance mode (suspendlistener).
How this will be seen by external mail servers?
Will they still send message to the faulty Ironport and get it bounced or will they know that this one is not rachable and send messages to one of the other?
Thanks
Arnaud
10-19-2009 09:17 AM
Just one more question:
Is there a risk that I loose emails?
Thanks
Arnaud
10-19-2009 10:12 PM
Just one more question:
Is there a risk that I loose emails?
10-20-2009 08:02 AM
Thanks for replying,
My question was more, what happens if one of the Ironport is out of order during a week end? Are Mail Servers going to try sending emails towards one of the 3 left or are they going to keep trying on the one that is faulty until they stop trying?
I'm asking this because we had a disk failure and one of the 4 was unavailable during 3 days but it was still declared on the DNS so I'm wondering if I lost any emails during that time.
I don't know if I'm clear enough on what I'm saying
Thanks
A.
10-20-2009 08:13 AM
Granted all your MX records have equal priority there is no risk as any MTA attempting delivery can only deliver to a host listening on port 25 for inbound SMTP connections, if unsuccessful it will attempt delivery to the next available record e.g. In this case if servers a,b, and c fail it will deliver to the next available servers, you will just simply have more inbound load on the other servers. I would recommend looking at something from Foundry Networks to load balance this more accurately and fail over as opposed to DNS RR.
Ordered IP addresses: (expiring at Tue Oct 20 09:37:10 2009 SAST)
Preference IPs
1 67.195.168.31
68.142.202.247
216.39.53.1
1 98.137.54.237
67.195.168.230
66.196.97.250
1 98.137.54.238
216.39.53.3
66.196.82.7
1 216.39.53.2
209.191.88.247
MX Records:
Preference TTL Hostname
1 1h56m17s a.mx.mail.yahoo.com
1 1h56m17s b.mx.mail.yahoo.com
1 1h56m17s c.mx.mail.yahoo.com
1 1h56m17s d.mx.mail.yahoo.com
1 1h56m17s e.mx.mail.yahoo.com
1 1h56m17s f.mx.mail.yahoo.com
1 1h56m17s g.mx.mail.yahoo.com
10-20-2009 11:04 AM
Thanks for your reply,
I just was not sure whether the mail servers would try another address or not.
Regarding the use of a load balancer, it would be difficult to implement given our architecture.
Thanks again
A.
10-21-2009 05:38 PM
I just was not sure whether the mail servers would try another address or not. Regarding the use of a load balancer, it would be difficult to implement given our architecture.
10-22-2009 11:07 AM
Indeed, we've got geographical diversity.
Thanks everyone, it helped me a lot
A.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide