Paypal error (6) Couldn't resolve host 'api-3t.paypal.com'

Hi - does anyone have any experience with this error and how to fix it?

Paypal error (6) Couldn't resolve host 'api-3t.paypal.com'

it is costing me orders :(

cheers, Mike

Check out the similar threads you'll find if you scroll down.

Have you reviewed the similar threads listed at the bottom of this posting?

kobra:

Have you reviewed the similar threads listed at the bottom of this posting?

unfortunately none match this specific error

dbltoe:

Check out the similar threads you'll find if you scroll down.

unfortunately none match this specific error

http://www.zen-cart.com/showthread.php?199020-%286%29-Couldn-t-resolve-host-api-3t-paypal-com

Does this help?

charmedbytina2:

http://www.zen-cart.com/showthread.php?199020-%286%29-Couldn-t-resolve-host-api-3t-paypal-com

Does this help?

Many thanks Tina - I copied the whole thread and sent it through on the trouble ticket currently in train with my host - they really don't like being told they have a problem do they? :)

cheers,
Mike
p.s. will let you know the result

Don't be afraid to point them to this curltester script for additional help: http://www.zen-cart.com/showthread.php?65680-PayPal-Communications-Response-Testing-Tools&p=434187#post434187 (saves them some trouble since using that they won't need to use your actual store to recreate the problem)

Hi Guys,

the issue magically resolved itself on that site - not sure whether something the host did (I doubt they did anything - they just said that their network is OK and the problem lies 'upstream') or something PayPal did in response to my technical ticket to which I had no response either:(

Now the SAME ISSUE is happening on another one of my sites which happens to be on the same server. Something I want to do is update the IP address that the cart resolves to at PayPAL to one of their newer addresses just to see if that solves the issue - now I know that this is NOT recommended (read it in the FAQ) but it may help me.

This response from host only a minute ago "I have tried pinging the site for a response from both our servers and our separate internet connection, and the request is timing out, showing me that it's an issue with PayPal."

So where can I change this? which file? any other advice? This same address is resolving from other sites I have that have the same PayPal account which was the same case yesterday - why would the address resolve from one site and not another ? all sites are on the same server.

The host did 'migrate' all their servers to a new platform on the day this issue started - coincidental or does that offer a clue?

cheers,
Mike

Not sure if I may have figured this out - I am now getting the same error across all 6 ZC sites I have with this host which migrated its servers to a new platform a few days ago when these issues began - the one site that is not having the issue now is the one which had the problem in the first place. With that site after a while I sent an eTicket to PayPal Technical Support - I didn't get a response but within a few hours the site was working OK.

Maybe because of the server migration PayPal is seeing something out of the norm with its 'Gateway' path from the server, different IP, maybe an IP redirect from the old servers or something like that and hence creates the error which when reported is corrected at their end say 'yes it is ok to use this gateway' ??

Any thoughts on that - does anyone know of similar circumstances or maybe when a Zenner changes hosts?

cheers,
Mike

shags38:

Not sure if I may have figured this out - I am now getting the same error across all 6 ZC sites I have with this host which migrated its servers to a new platform a few days ago when these issues began - the one site that is not having the issue now is the one which had the problem in the first place. With that site after a while I sent an eTicket to PayPal Technical Support - I didn't get a response but within a few hours the site was working OK.

Maybe because of the server migration PayPal is seeing something out of the norm with its 'Gateway' path from the server, different IP, maybe an IP redirect from the old servers or something like that and hence creates the error which when reported is corrected at their end say 'yes it is ok to use this gateway' ??

Any thoughts on that - does anyone know of similar circumstances or maybe when a Zenner changes hosts?

cheers,
Mike

THIS WORKS - submitting a ticket to Paypal Technical support has the issue sorted almost instantaneously so my theory above is correct - they do not send a response perse other than a report log back as a receipt of your query - I think their system must be automated, reading the data entered on a form and sending a ping or something and correcting the gateway.

So the quick fix for this is go to https://ppmts.custhelp.com/app/ask and complete the 'ask a question' form - the issue will be fixed pronto.

Maybe add this solution in a PayPal FAQ ?

cheers,
Mike

shags38:

This response from host only a minute ago "I have tried pinging the site for a response from both our servers and our separate internet connection, and the request is timing out, showing me that it's an issue with PayPal.

Pinging PayPal is NOT a valid check to see if it is accessible or not. Even when it's all working the pings will show a 100% packet loss.

tracert or traceroute are much better tools for this job.

Cheers
Rod

shags38:

THIS WORKS - submitting a ticket to Paypal Technical support has the issue sorted almost instantaneously
<snip>
So the quick fix for this is go to https://ppmts.custhelp.com/app/ask and complete the 'ask a question' form - the issue will be fixed pronto.

Nothing wrong with this 'quick fix' tip, but you may have just been lucky. It could be that your host/network was blocked by PayPal (such blockings are generally 'transient' being added and removed dependent on activity) and that as a result of your report the block was automatically removed (it may only be temporary, depending why it was blocked in the 1st place). It could even just be coincidental timing too. Time will tell.

I'm not trying to ruin your day or anything, just trying to caution you to not be too confident at this stage. I'd be keeping a close watch on things for the next few days, at least.

Cheers
Rod

shags38:

Maybe because of the server migration PayPal is seeing something out of the norm with its 'Gateway' path from the server, different IP, maybe an IP redirect from the old servers or something like that and hence creates the error which when reported is corrected at their end say 'yes it is ok to use this gateway' ??No, not relevant.
(Only exception would be if you were using advanced fraud management filters and payflow and you had specifically instructed your payflow account to only accept transactions from a certain IP. That has nothing to do with Zen Cart at all. That must be sorted out with PayPal yourself.)

shags38:

does anyone know of similar circumstances or maybe when a Zenner changes hosts?
There is nothing host-specific about how Zen Cart interacts with PayPal.
And there is nothing IP-specific about how Zen Cart connects to PayPal. Zen Cart has always used PayPal's name-based addresses specifically so that there would never be any IP-specific changes needed to Zen Cart no matter what PayPal does to their servers.

shags38:

does anyone know of similar circumstances or maybe when a Zenner changes hosts?

Initial thoughts were that DNS propagation delays could explain it, but that can't be the case. PayPal doesn't need to resolve your host's IP address because that is a part of the data packets that it receives.

To me, it still looks like a DNS issue though. "Couldn't resolve host 'api-3t.paypal.com'" is pretty specific. The real question is why couldn't the host be resolved?

Cheers
Rod

RodG:

To me, it still looks like a DNS issue though. "Couldn't resolve host 'api-3t.paypal.com'" is pretty specific. The real question is why couldn't the host be resolved?
Agreed. Usually that suggests a flaw in the server's resolv.conf settings, or related subsystems.

Thanks for your responses so far

here is an update - my host and PayPal technical support are pointing to it being a script problem with ZenCart - see comments below;

from my host only minutes ago -

As for the issue yourself, I really don't think migrating is going to solve the problem. We've shown that DNS lookups are working and that it's possible for you to connect to the Paypal's API and also that curl does work to connect (see my curl -i command I ran earlier in this ticket).

It's looking more and more like an issue with the way zen cart use CURL. Can you ask them to run troubleshooting on it?

from PayPal Tech Support a few hours ago;

looks good so far. But its definitely not on our Site the issue. I checked again with our network Team.
You are not blocked. Manually you can connect.

Being able to resolve our domain (either https://www.paypal.com, api-3t.paypal.com or otherwise) via manual tools such as 'host' or 'dig' indicates that DNS resolution works and that our nameservers are properly propagating the A-record for our domains.

I am unfortunately not sure why this doesn't appear to be working for you as part of your integration - but because manual tests check out correctly, this points directly at an error with the application / script you're using.

Have you tried using our PayPal SDK's directly by any chance? You can find these at the following link; https://paypal.github.io/
I'd be interested to find out whether these fail to resolve as well.

every test known to man has been done over the past 5 days now - tracerts from different servers at the host, and other route traces, API checks etc - I wont add them to this post as it would take up page after page. Essentially my host is resolving to PayPal.

My naive assertion of the simple fix in a previous post was delusional - I made the mistake of not checking past step 1 of the checkout process where the error occurred with a couple of sites in the first instance, so if it didn't occur at step 1 I didn't look further - only yesterday did I do a step by step check on all my sites - it can happen at the end of step 2 (continue) as I discovered where it reverts back to login page (https://www.mysite.com/index.php?main_page=login) with an error message that is similar to the wording of the error (6) but doesn't use that terminology "Error An error occurred when we tried to contact the payment processor. Please try again, select an alternate payment method, or contact the store owner for assistance. ( )".

Through doing this I discovered all 9 of my eCommerce sites (all ZC) on the server were affected and had been since Friday 14th.

Factors that don't quite fit the ZC script thing - not that it should arbitrarily be discounted - (a) Host migrated all their servers to a new platform on 14th June, the day the problems started (b) one ZC domain on the hosts U.S.A. server works fine, no problems and it is a 100% 'clone' of one of the sites on the Australian server - copied from a .com.au domain and uploaded onto a .com domain, absolute mirror copy. (c) cPanel upgraded 8 days ago at my host - one tech at host (have been dealing with 3 of them) said it may be a Curl problem - see this link "I've running a few tests as there may be a bug with CURL which could be causing this problem: http://sourceforge.net/p/curl/bugs/1247/ " - apparently they cannot revert to a previous version of CURL just for a test to see if in fact that is the issue.

I am having some of my sites migrated to their U.S. server to see if that solves the issue - their operation in the U.S. is using a different platform. One huge problem I have is that 3 of my better performing sites cannot be hosted on a U.S. server because of previous a DMCA issue (trademark related). The other issue is if I move these particular domains to another cPanel host will they have a different version of CURL operating or does cPanel upgrade every client globally simultaneously ?

If there are specific tracert or other reports you want to see please let me know.

In conclusion (ooops, shouldn't use that term, this issue is far from concluded), as much as I am doubtful there is a ZC scripting issue is there any tests that can be done to determine this? In my admin on one site only I deleted PayPal and reinstated it to see if that made a difference but it didn't.

If indeed there is something I should try then please be detailed on how I should do it - I am not a puter tech or coder :)

looking forward to assistance here.

cheers,
Mike

shags38:

Through doing this I discovered all 9 of my eCommerce sites (all ZC) on the server were affected and had been since Friday 14th.

Factors that don't quite fit the ZC script thing - not that it should arbitrarily be discounted - (a) Host migrated all their servers to a new platform on 14th June, the day the problems started
Agreed. The only thing that changed between when it WAS WORKING FINE USING ZEN CART CODE was the servers. Thus, it's unrealistic to point to Zen Cart as being the culprit.

I repeat my previous post: your server's name resolution is busted. Or at least how your server is configured for CURL anyway.

For simplified testing, just use your curltester.php script with the paypal=1 parameter as described here:
http://www.zen-cart.com/showthread.php?65680-PayPal-Communications-Response-Testing-Tools&p=434187#post434187

Hint: That file contains a standalone copy of all the same logic used by Zen Cart when doing CURL connections to PayPal.

DrByte:

Agreed. The only thing that changed between when it WAS WORKING FINE USING ZEN CART CODE was the servers. Thus, it's unrealistic to point to Zen Cart as being the culprit.

I repeat my previous post: your server's name resolution is busted. Or at least how your server is configured for CURL anyway.

Thanks for the quick response Doc - Strangely one tech suggested a potential problem with CURL as I mentioned - but apparently I am the only client having this issue (yes I have heard that before) but I put it out on an independent forum here in Oz and no-one has responded saying they too are experiencing the problem - the tech at PayPal said they have no other reports at present ............. is it possible I have been infected by some sort of worm that is targeting specifically payment scripts - clutching at straws but I'm sure you can see why - 9 eCommerce sites all not functioning for nearly 6 days now and no-one has answers after 3 trees worth of pages of tests and emails ?

cheers,
Shags