copyright 2014 1 Docker, DevOps, Security Chris Swan, CTO @cpswan Cloud native networking
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
copyright 2014 1
Docker, DevOps, Security
Chris Swan, CTO
@cpswan
Cloud native networking
copyright 2014 2
TL;DR
Dockerfile is awesomely productive
Great for DevOps
Containers don’t contain
At least not yet
Images have a manifest problem
Keep track of your stuff
copyright 2014 3
Why me?
copyright 2014 4
copyright 2014 5
Let’s start with a demo
copyright 2014 6
Containers don’t contain
copyright 2014 7
With thanks to Dan Walsh @rhatdan
Watch his DockerCon 2014 presentation at http://is.gd/dcrhdw
copyright 2014
Shocker
8
The issue
The response
http://stealth.openwall.net/xSports/shocker.c
https://news.ycombinator.com/item?id=7910117
copyright 2014
Because containers aren’t VMs
and this has yet to come:
9
copyright 2014
Possible to have our cake and eat it?
10
copyright 2014
cgroups
11
copyright 2014
namespaces
mnt mount points, filesystems
pid processes
net network
ipc inter process communication
uts hostname
device devices
user UIDs 12
copyright 2014
capabilities
Fine grained control over ‘root’ privileges:
• deny all "mount" operations;
• deny access to raw sockets (to prevent packet
spoofing);
• deny access to some filesystem operations, like
creating new device nodes, changing the owner of files,
or altering attributes (including the immutable flag);
• deny module loading;
• etc.
13
copyright 2014
Mandatory Access Control (MAC):
AppArmor and SELinux
14
copyright 2014
Containers will contain
• Use of namespaces, capabilities and MAC will
improve • Might be a game of ‘whack a mole’
• Hard to tell when we’re done (is @solomonstre’s word going to
be enough?)
• Libcontainer can drive other mechanisms • More secure options might come
• Hardware support might come • Existing rings 1 & 2 aren’t used much, but aren’t really suitable
• VT-x introduced ring -1, do we need a ring 0.5?
15
copyright 2014 16
The manifest problem
copyright 2014
My Dockerfile from earlier
17
copyright 2014
Each active line creates a layer
18
Base OS
Sources
Update repos
Install nginx
Mod nginx.conf
Mod index.html
copyright 2014
An image binds layers together
19
Base OS
Sources
Update repos
Install nginx
Mod nginx.conf
Mod index.html
copyright 2014
Nginx example
The image is the unit of deployment
20
copyright 2014
Nginx example
What version of nginx is that?
21
copyright 2014
Nginx example
What version of OpenSSL installed?
22
?
copyright 2014
Problem 1 – non determinism
Whilst we want this to be cached in the short term:
apt-get install nginx
We perhaps don’t want it cached in the long term
What are those durations?
23
copyright 2014
2 – the manifest problem
When I run
apt-get install nginx
I don’t know which version of nginx I just got
Should I?
nginx –v > some_log.txt
Or maybe?
apt-cache policy nginx > some_log.txt
24
copyright 2014 25
TL;DR
Dockerfile is awesomely productive
Great for DevOps
Containers don’t contain
At least not yet
Images have a manifest problem
Keep track of your stuff
copyright 2014 26
Please give me feedback:
http://is.gd/chdmsf
Related Documents
