I am configuring a new web application server running Ubuntu 16.04. The only thing "unusual" I have done is install php 5.6 instead of php7. Php5.6 however does require a valid root certificate and I am getting errors in a variety of apps that care about this. Curl, cron, etc.
I have tried a variety of fixes to get this resolved with no improvement. Such as:
https://github.com/composer/composer/issues/3346#issuecomment-76593763
How do I install a root certificate?
Still no luck. The cron job I am running still generates:
curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none
More details here: http://curl.haxx.se/docs/sslcerts.html
curl performs SSL certificate verification by default, using a "bundle" of Certificate Authority (CA) public keys (CA certs). If the default bundle file isn't adequate, you can specify an alternate file using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in the bundle, the certificate verification probably failed due to a problem with the certificate (it might be expired, or the name might not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) option.