After upgrade to 14.4.5801 my server bandwidth double
Problem reported by Sérgio Rocha - January 18, 2016 at 11:06 AM
Known
Hi everyone,
 
We did the upgrade for 14.4.5801 at the end of December, and after that my server bandwidth consumption doubled.
In the first weeks we think that was because the IMAP modifications, but after a month the bandwidth stays the double, mainly in HTTPs (Active Sync)
 
Its just a coincidence?
 
Regards,
 
Sergio
 

20 Replies

Reply to Thread
1
Ray Cook Replied
I have 4 domains where IMAP bandwidth for one or two users has gone up by an order of magnitude. I am investigating what combination of operating system / mail client might have caused this. For example, one account used to have a few 100k of bandwidth per day - now it's 20gb - this can't be down to that user. they have very little email traffic compared to other users whose bandwidth has stayed the same.
 
1
Sérgio Rocha Replied
Hi,
 
We had a few like that, using the firewall log we found the top user for the email service.
We contact the clients IT to help find the user generating the problem. We had this problem with IMAP and Active Sync users.
After deletion and recreation everything get normal.
 
Regards,
 
 
 
 
0
Ray Cook Replied
Thanks - what did you delete - the account in SM or the account at the client side?
2
Ray Cook Replied
Does anyone have an answer to this? We just added some new IMAP users and their bandwidth is very high. But one of our users has now used >100gb in a week which is nonsense. They receive and send no more than 10 emails a day and they use 400mb disk space. What could cause that?
0
Paul Blank Replied
These reports are troublesome indeed. Can anyone verify that actual bandwidth is being used, and it's not just reported (and not-really-used) bandwidth? If the bandwidth usage is real, the thought of outrageous cell phone bills - and who gets the blame - is scary, not to mention the effect of that traffic on the email server and network infrastructure.
 
Seems to me, though, that if the usage is real, the traffic might just be contained within the mail server; still not a good scenario, but "better", I guess, than wild network traffic.
 
From what I've read on the forum, some folks have fixed these issues by deleting and re-creating the email accounts; that's still a lot of work that should not be necessary, finding out which accounts are responsible etc. etc.
1
Sérgio Rocha Replied
Hi,
 
This is real problem, special in Portugal where most of offices have more that 100 Mbits of bandwidth, we had an 300Mbits more than usual. Just one client was originating more that 70 Mbits
 
 
1
Ray Cook Replied
So it seems that we are not the only ones experiencing this problem - can Smartertools provide an definitive response?
0
Paul Blank Replied
Looks as if my question about this was answered - seems like the bandwidth is out there on the 'net as well. This appears to need immediate attention, and will certainly put off my upgrading yet again.
 
0
Paul Blank Replied
Thanks for posting!!
1
Employee Replied
Employee Post
This is due to a fix we needed to implement for IMAP which was causing issues syncing mail with Outlook 2016.
 
The issue was that we were issuing folder ID's with a value of 0 which isn't allowed by the IMAP specification.  Other IMAP clients including Outlook never had an issue with this, but when Outlook 2016 was released is gave errors due to this bug, particularly when trying to move messages between folders.
 
So we had to change any folders that had an ID of 0 to a non zero number.  Unfortunately that signals IMAP clients that the folder is different than the one they were previously synced with that had the same name, and the IMAP client will proceed to re-sync / re-download all messages in that folder.
 
To avoid a server from being crushed with a huge number of IMAP folder re-syncs, SmarterMail rolls this fix out at a rate of 10 users per hour.  Until all IMAP clients have resynced their messages, the server bandwidth usage will be higher.  There was no way around this.
0
Paul Blank Replied
Bryon, it still seems like an inordinately large amount of traffic for admins who claim to have users with relatively small accounts and not so much used storage. And why do these problems reportedly seem to go away (per user) when accounts are deleted and re-created?
0
Paul Blank Replied
There also appear to be other issues with Outlook 2016 (g-d bless Microsoft), and SM needs to get into line with those as well, until Outlook changes yet again.
0
Sérgio Rocha Replied
Hi Bryon,

The supposed behaviour its sync once, not forever, and what we see is that the clients with this problem never stop to download email messages.

We saw this in a few client and the Outlook only stop to download messages after we delete the account and add again. After this the outlook sync just once more.

The problem is that something is making the outlook (2013) download in loop.

The first client we use to troubleshoot have an account of 3 GB and we had the client download for 3 weeks, 10 hours/day at 70 Mbits !!!

This is not the expected behaviour.
0
Paul Blank Replied
QED .. sigh ..
0
Ray Cook Replied
Yes, I think the issue goes beyond the immediate one of resynching required due to the upgrade. There do seem to be accounts which don't just synch once, but forever and there does not appear to be any specific mail client where this is a factor other than the issue is with 'Outlook' - there must be some other factor in the communication between SM and the mail client.

We can all blame Microsoft but we need a solution that will work. Deleting and adding back seems to be the best answer so far and I am waiting for our 120gb per week (LOL) customer to do this and will report back on the result.

However, I suspect that for SM users who have a large number of IMAP accounts this could be a bit of a nightmare. We have 100+ but not all are showing high usage.

Some IMAP accounts that I would expect to show higher bandwidth than our 120gb man show only 1 or 2gb per day not 25gb. No idea why his is so high compared to others.

I wonder if it would be easier for Smartertools to accept there is an issue and find out whether there is any fix that can be introduced to SM itself or talk to Microsoft about it to find a solution.

Luckily, so far, we have not reached a bandwidth threshold that would penalise us financially, but I can see this might be a problem for others and potentially some phone users.
2
Paul Blank Replied
(Ray Cook said)
..  I wonder if it would be easier for Smartertools to accept there is an issue and find out whether there is any fix that can be introduced to SM itself or talk to Microsoft about it to find a solution ...
 
Thanks, Ray.  I could not have said that better.
 
1
Ray Cook Replied
Well, the fix for this issue appears to be to delete the account and add it back. This does not explain why it affects some users more than others but at least it can be fixed.
 
However, the account that was reporting 25gb IMAP traffic each day is now reduced to a few 10s of kb!
 
Nevertheless, if you have a large number of accounts with reported high IMAP traffic, it may take some time to persuade them to delete and add back their account.
0
Paul Blank Replied
It is not really acceptable that this happens at all, but as you say, at least there appears to be a fix.
0
Sérgio Rocha Replied
Good luck! Hard time we had, and after that the secound wave was active sync devices that stop sync. Same work around delete account and config again.
0
Paul Blank Replied
ST, would you kindly comment on these issues?  A client is waiting on some kind of resolution to this matter (besides deleting and re-creating accounts) before upgrading.  Thanks!
 

Reply to Thread