If you try to sudo apt-get install iptables-persistent on you may get this error:

root@mothership:~# apt-get install netfilter-persistent
Reading package lists... Done
Building dependency tree
Reading state information... Done
netfilter-persistent is already the newest version.
The following package was automatically installed and is no longer required:
  bind9utils
Use 'apt-get autoremove' to remove it.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up netfilter-persistent (1.0.3) ...
update-rc.d: warning: start and stop actions are no longer supported; falling back to defaults
A dependency job for netfilter-persistent.service failed. See 'journalctl -xn' for details.
invoke-rc.d: initscript netfilter-persistent, action "start" failed.
dpkg: error processing package netfilter-persistent (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of iptables-persistent:
 iptables-persistent depends on netfilter-persistent (= 1.0.3); however:
  Package netfilter-persistent is not configured yet.

dpkg: error processing package iptables-persistent (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 netfilter-persistent
 iptables-persistent
E: Sub-process /usr/bin/dpkg returned an error code (1)

Sep 02 18:45:31 mothership.installgentoo.com systemd-modules-load[12122]: Failed to lookup alias 'ipmi_poweroff':
Sep 02 18:45:31 mothership.installgentoo.com systemd-modules-load[12122]: could not open moddep file '/lib/module
Sep 02 18:45:31 mothership.installgentoo.com systemd-modules-load[12122]: Failed to lookup alias 'ipmi_si': Funct
Sep 02 18:45:31 mothership.installgentoo.com systemd-modules-load[12122]: could not open moddep file '/lib/module
Sep 02 18:45:31 mothership.installgentoo.com systemd-modules-load[12122]: Failed to lookup alias 'ipmi_watchdog':
Sep 02 18:45:31 mothership.installgentoo.com systemd[1]: systemd-modules-load.service: main process exited, code=
Sep 02 18:45:31 mothership.installgentoo.com systemd[1]: Failed to start Load Kernel Modules.

To resolve you have to edit the file:

/usr/lib/modules-load.d/ipmievd.conf

and comment out like so:

#ipmi_devintf
#ipmi_msghandler
#ipmi_poweroff
#ipmi_si
#ipmi_watchdog

then reboot

After you sudo apt-get install nginx-full and you get this:

nginx: Setting up nginx-full (1.9.2-1) ...
nginx: Starting nginx: nginx failed!
nginx: invoke-rc.d: initscript nginx, action "start" failed.
nginx: dpkg: error processing nginx-full (--configure):
nginx: subprocess installed post-installation script returned error exit status 1
nginx: dpkg: dependency problems prevent configuration of nginx:
nginx: nginx depends on nginx-full (>= 1.9.2-1) | nginx-light (>= 1.9.2-1) | nginx-extras (>=
1.9.2-1); however:
nginx: Package nginx-full is not configured yet.
nginx: Package nginx-light is not installed.
nginx: Package nginx-extras is not installed.
nginx: nginx depends on nginx-full (<< 1.9.2-1.1~) | nginx-light (<< 1.9.2-1.1~) | nginx-extras
(<< 1.9.2-1.1~); however:
nginx: Package nginx-full is not configured yet.
nginx: Package nginx-light is not installed.
nginx: Package nginx-extras is not installed.
nginx:
nginx: dpkg: error processing nginx (--configure):
nginx: dependency problems - leaving unconfigured
nginx: Errors were encountered while processing:
nginx: nginx-full
nginx: nginx
nginx: E: Sub-process /usr/bin/dpkg returned an error code (1)
Failed nginx install.
Skipped nginx config, due to presence in failed steps
1 steps selected, 1 failed.
Failed steps: nginx

All you need to do is remove:

listen [::]:80 default_server;

from /etc/nginx/sites-enabled/default.

This is caused if you server does not support IPv6 but nignx is trying to listen on it.

After installing node.js and npm and you go to run a node application you get this error:

sh: 1: node: not found
npm ERR! error installing chokidar@0.4.0
npm WARN This failure might be due to the use of legacy binary "node" 
npm WARN For further explanations, please read
npm WARN /usr/share/doc/nodejs/README.Debian
npm WARN

This is because in debian nodejs installs to /usr/bin/nodejs while the script/program is looking for /usr/bin/node.

To fix just run:

sudo ln -s /usr/bin/nodejs /usr/bin/node