I am receiving a 502 bad gateway error but only on configurable products. Below is the ngnix log.
We are running Magento 1.9.1.0 with all plugins disabled and this error still occurs with the default theme.
2015-01-23 11:49:21 UTC 2015/01/23 11:49:21 [error] 5393#0: *14926882 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 123.45.678.912, server: mywebsite.co.uk, request: "POST /checkout/cart/add/uenc/aHR0cDovL2Rldi50b3dlci1oZWFsdGguY28udWsvY2lyY3VsYXRpb24tcHJvLmh0bWw,/product/762/form_key/R7HvodwFx4M1C0hR/ HTTP/1.1", upstream: "fastcgi://unix:/tmp/php5-fpm-usernm.sock:", host: "dev.mywebsite.co.uk", referrer: "http://dev.mywebsite.co.uk/product.html"
The PHP errors are as follows...
child 15937 exited on signal 11 (SIGSEGV) after 29.994150 seconds from start
child 16194 started
(Unable to comment due to low points)
Anyway, we had this issue as well with configurable products, and it turned out to be an issue with one of our product price rules. We are running Enterprise edition, and Magento provided us with a patch. I'm not sure if the CE version has a support team available or not though.
I would check your shopping cart rules and try determining if one of them is the culprit by disabling the rules one at a time.
This may be linked to https://magento.stackexchange.com/questions/37395/magento-debug-trace/44112#44112
Configurable products would throw a 502 Bad Gateway when adding to cart. Was linked to a Shopping Cart Rule that included a subselection of products.
Implemented the following solution:
app/code/core/Mage/SalesRule/Model/Rule/Condition/Product/Subselect.php on approx line 114:
**From:** if (parent::validate($item)) {
**To:** if (Mage_Rule_Model_Condition_Combine::validate($item)) {