package redis-server 2:2.8.19-3 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

I second this bug. Something is badly off with redid-server latest release:

Setting up redis-server (2:3.0.6-1) ...
insserv: script redis-server: service redis-server already provided!
insserv: exiting now!
update-rc.d: error: insserv rejected the script header
dpkg: error processing package redis-server (--configure):
 subprocess installed post-installation script returned error exit status 1

After failed install attempt:
# ls -l /etc/init.d/redis-server
-rwxr-xr-x 1 root root 1750 Dec 19 2015 /etc/init.d/redis-server

Removing the failed package:
# apt-get remove redis-server

# ls -l /etc/init.d/redis-server
-rwxr-xr-x 1 root root 1750 Dec 19 2015 /etc/init.d/redis-server
# dpkg -S /etc/init.d/redis-server
redis-server: /etc/init.d/redis-server

No change! The file is still there.

Status changed to 'Confirmed' because the bug affects multiple users.

Issue on my server was NOT caused by redid-server package.

There was another script with following header in /etc/init.d/ -script:
#!/bin/bash
### BEGIN INIT INFO
# Provides: redis-server
# Required-Start: $syslog $remote_fs
# Required-Stop: $syslog $remote_fs
# Should-Start: $local_fs
# Should-Stop: $local_fs
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: redis-server - Persistent key-value db
# Description: redis-server - Persistent key-value db
### END INIT INFO

That script had nothing to do with Redis or redid-server package. Updating that fixed my machine.