How to start/stop iptables on Ubuntu?

I don’t know about “Ubuntu”, but in Linux generally, “iptables” isn’t a service – it’s a command to manipulate the netfilter kernel firewall. You can “disable” (or stop) the firewall by setting the default policies on all standard chains to “ACCEPT”, and flushing the rules. iptables -P INPUT ACCEPT iptables -P OUTPUT ACCEPT iptables -P … Read more

How do I auto-start docker containers at system boot?

Apparently, the current method to auto-start Docker containers (from Docker 1.2) is to use restart policies. This will control how Docker should handle starting of the container upon startup and re-starting of the container when it exits. I’ve used the ‘always’ option so far, and can confirm that it makes Docker auto-start the container at … Read more

How do I get apt-get to ignore some dependencies?

Simple and easy solution: just specify the unwanted packages with an extra – after each of them. Example without the – switch: root@debian:~# apt-get install bsd-mailx Reading package lists… Done Building dependency tree Reading state information… Done The following extra packages will be installed: exim4-base exim4-config exim4-daemon-light liblockfile-bin liblockfile1 […] Example using the switch to … Read more

How to view all ssl certificates in a bundle?

http://comments.gmane.org/gmane.comp.encryption.openssl.user/43587 suggests this one-liner: openssl crl2pkcs7 -nocrl -certfile CHAINED.pem | openssl pkcs7 -print_certs -text -noout It indeed worked for me, but I don’t understand the details so can’t say if there are any caveats. updated june 22: for openssl 1.1.1 and higher: a single-command answer can be found here serverfault.com/a/1079893 (openssl storeutl -noout -text -certs … Read more