IMAP IDLE 5 minutes instead of 30?

short/y · 4 Jun 2010, 06:19 AM

I'm using K9Mail on my Android phone. It supports IMAP IDLE with timeouts of varying intervals. Fastmail documentation (http://www.fastmail.fm/docs/imap/thunderbird.htm) says to set the timeout to 30 minutes or less but my connection is getting reset after 5 minutes. I've "proven" this to myself by setting the timeout for 6 minutes and, after 5 minutes, the connection gets closed ("Connection reset by peer") whereas if I set the timeout for 3 minutes, everything works fine and I get no connection resets.

This isn't really a big deal -- I can live with a 3 minute timeout -- but I'm curious if this might be a bug, either on the Fastmail side or the K9 side. If it's a K9 bug, I'll report it to them but I kind of need someone knowledgeable about the Fastmail side to respond.

n5bb · 5 Jun 2010, 10:36 AM

If you do a web search you will find a lot of discussion about this issue (mobile IMAP IDLE timeouts). It appears that most mobile networks have a timeout on their NAT gateway of about 5 minutes (for Verizon, for example). If the mobile device sends a NOOP (no operation) command at least every 5 minutes, then if the mobile connection isn't lost due to other reasons you should be OK.

So depending on your point of view it's a problem with the mobile network provider or the mobile phone, I think.

Bill

short/y · 6 Jun 2010, 01:10 AM

Thanks for the reply Bill! After an hour our so of searching, I didn't see anything like what you describe but perhaps I didn't formulate my search appropriately. Anyway, I've got another provider (tuffmail) that doesn't timeout with a 24 minute interval

so I don't think it's my cellular provider. I guess mauve I've answered my own question, eh? If tuffmail doesn't timeout and fastmail does then it would seem fastmail has some sort of problem. But then I would think there would be more reports of the issue.

beq · 6 Jun 2010, 02:31 PM

Quote:

Originally Posted by short/y

After an hour our so of searching, I didn't see anything like what you describe but perhaps I didn't formulate my search appropriately.

I wish the forum could at least be improved with an AND search, see:
http://www.emaildiscussions.com/showthread.php?t=56835

DrStrabismus · 6 Jun 2010, 09:00 PM

Quote:

Originally Posted by short/y

Thanks for the reply Bill! After an hour our so of searching, I didn't see anything like what you describe but perhaps I didn't formulate my search appropriately. Anyway, I've got another provider (tuffmail) that doesn't timeout with a 24 minute interval

so I don't think it's my cellular provider. I guess mauve I've answered my own question, eh? If tuffmail doesn't timeout and fastmail does then it would seem fastmail has some sort of problem. But then I would think there would be more reports of the issue.

I suspect that Tuffmail is using a server-side workaround. I think most IMAP servers added an option to help them workaround an Outlook bug by sending dummy updates. My guess is that Tuffmail have retuned this to help keep mobile connections alive without the end user having to configure it in the client.

4 Jun 2010, 06:19 AM	#1
short/y Junior Member Join Date: Aug 2006 Location: Silly-con Valley, CA Posts: 7	IMAP IDLE 5 minutes instead of 30? I'm using K9Mail on my Android phone. It supports IMAP IDLE with timeouts of varying intervals. Fastmail documentation (http://www.fastmail.fm/docs/imap/thunderbird.htm) says to set the timeout to 30 minutes or less but my connection is getting reset after 5 minutes. I've "proven" this to myself by setting the timeout for 6 minutes and, after 5 minutes, the connection gets closed ("Connection reset by peer") whereas if I set the timeout for 3 minutes, everything works fine and I get no connection resets. This isn't really a big deal -- I can live with a 3 minute timeout -- but I'm curious if this might be a bug, either on the Fastmail side or the K9 side. If it's a K9 bug, I'll report it to them but I kind of need someone knowledgeable about the Fastmail side to respond.

5 Jun 2010, 10:36 AM	#2
n5bb Intergalactic Postmaster Join Date: May 2004 Location: Irving, Texas Posts: 8,929	If you do a web search you will find a lot of discussion about this issue (mobile IMAP IDLE timeouts). It appears that most mobile networks have a timeout on their NAT gateway of about 5 minutes (for Verizon, for example). If the mobile device sends a NOOP (no operation) command at least every 5 minutes, then if the mobile connection isn't lost due to other reasons you should be OK. So depending on your point of view it's a problem with the mobile network provider or the mobile phone, I think. Bill

6 Jun 2010, 01:10 AM	#3
short/y Junior Member Join Date: Aug 2006 Location: Silly-con Valley, CA Posts: 7	Thanks for the reply Bill! After an hour our so of searching, I didn't see anything like what you describe but perhaps I didn't formulate my search appropriately. Anyway, I've got another provider (tuffmail) that doesn't timeout with a 24 minute interval so I don't think it's my cellular provider. I guess mauve I've answered my own question, eh? If tuffmail doesn't timeout and fastmail does then it would seem fastmail has some sort of problem. But then I would think there would be more reports of the issue.