I have launched new Debian 8.2 VPS. I could easily do this:
curl -I https://api.twilio.com HTTP/1.1 200 OK Access-Control-Allow-Credentials: true Access-Control-Allow-Headers: Accept, Authorization, Content-Type, If-Match, If-Modified-Since, If-None-Match, If-Unmodified-Since Access-Control-Allow-Methods: GET, POST, DELETE, OPTIONS Access-Control-Allow-Origin: * Access-Control-Expose-Headers: ETag Content-Length: 558 Content-Type: application/xml Date: Sun, 24 Jan 2016 20:31:30 GMT Strict-Transport-Security: max-age=15768000 Twilio-Request-Duration: 0.002 Twilio-Request-Id: RQf68d83772cbb45fda8ee44f4e1b864a5 X-Powered-By: AT-5000 X-Shenanigans: none Connection: keep-alive Then I have upgraded the system: apt-get update The following packages will be upgraded: apt apt-utils base-files bind9-host ca-certificates dnsutils dpkg file grub-common grub-pc grub-pc-bin grub2-common host isc-dhcp-client isc-dhcp-common krb5-locales libapt-inst1.5 libapt-pkg4.12 libbind9-90 libc-bin libc6 libdns-export100 libdns100 libfuse2 libgdk-pixbuf2.0-0 libgdk-pixbuf2.0-common libgssapi-krb5-2 libirs-export91 libisc-export95 libisc95 libisccc90 libisccfg-export90 libisccfg90 libk5crypto3 libkrb5-3 libkrb5support0 libldap-2.4-2 liblwres90 libmagic1 libpam-modules libpam-modules-bin libpam-runtime libpam0g libpcre3 libpng12-0 libssl1.0.0 libsystemd0 libudev1 libxml2 linux-image-3.16.0-4-amd64 locales login multiarch-support openssh-client openssh-server openssh-sftp-server openssl passwd perl perl-base perl-modules python-pygments rsyslog systemd systemd-sysv udev 66 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 78.3 MB of archives. After this operation, 592 kB disk space will be freed. Do you want to continue? [Y/n] Processing triggers for ca-certificates (20141019+deb8u1) ... Updating certificates in /etc/ssl/certs... 19 added, 18 removed; done. Running hooks in /etc/ca-certificates/update.d....done. curl -I https://api.twilio.com curl: (60) SSL certificate problem: self signed certificate in certificate chain More details here: http://curl.haxx.se/docs/sslcerts.html and even with this: wget http://curl.haxx.se/ca/cacert.pem curl -I --cacert cacert.pem https://api.twilio.com there is same error. So the problem is in the package ca-certificates removing 18 certificates, and disturbing the previous workable and stable system. The ca-certificates package MUST ask the user if to remove the previously used files or not. I would like to know which certificates are removed to put them back simply, for system to work.
