Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm facing a strange issue. My vps from Linode has no issue connecting to apple push server with following command.

openssl s_client -connect -cert Test_dev_apns_cert.pem -key Test_dev_apns_key.pem

However, I was using the same pem files with above command testing from my another low budget vps and I'm getting this:

Verify return code: 20 (unable to get local issuer certificate)

Both are running Ubuntu 11.04 and installed LAMP as usual. No special configuration is done to both servers for SSL. Am I missing something here?

share|improve this question

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.