A small security firm in Iowa says it has discovered why Yahoo’s email is sometimes slow.
An analysis of Yahoo Inc. mail servers found that they were only able to accept email about half the time on average, making it likely that email was taking longer than normal to deliver, the security firm said Friday.
In testing 16 Yahoo mail servers, Dymeta Inc., based in Bettendorf, Iowa, found on average that the servers were unable to accept email 45 percent of the time, and the number of available servers ranged from as low as four to as high as 12, Aaron Gillette, chief technician for the company, said.
“We’re not saying that mail isn’t going to get through, but it’s likely to take longer than normal,” Gillette said. “Normally, when you send email from one account to another, you can expect it to be delivered in minutes. With the problems they’ve got, it could take hours or even days to get through, or it could be bounced back entirely.”
Finding’s :
First, Mail Server Profiler mapped and analyzed the Yahoo Mail setup. It found 16 host IP addresses behind four mail server MX records, and identified half of them as closed, ie, not accepting any email messages.
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Next, they took measurements every two minutes for half an hour. That’s 15 separate readings of each of 16 IP addresses, for a total of 240 readings. The results were surprising.
During that period, Yahoo mail servers were willing to accept mail just 55% of the time (133 “open” readings). Average availability for MX record groups over the period ranged from as low as 25% to a high of just 75%.
**MX Server Group Availability**
mx1.mail.yahoo.com 63%
mx2.mail.yahoo.com 75%
mx3.mail.yahoo.com 41%
mx4.mail.yahoo.com 25%
All Mail Servers 55%
In fact, only one of the 16 hosts was open for every reading. The worst host was available 7% of the time.
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End User :
What does this mean to the average sender? Many network managers set their email serving software to re-try sending four times, at increasing intervals. For example, after the first attempt, you may try again in 10 minutes. If that attempt fails, try again an hour later… again in 4 hours … and last attempt, 10 hours after that.
If your chances of delivery are less than 60% each time you try, you may fail to get messages delivered at all. In the meantime, as ever more undelivered mail piles up in its delivery queue, your server will waste more and more storage, bandwidth and cpu cycles trying to ship the messages. Bad karma.
So what’s the answer? Paying customers who don’t want to maintain their own in-house mail servers, but still like reliable email, may want to consider moving their accounts to healthier environs.