*CLOSED* Good way to isolate VE networks. [message #10817] |
Sun, 04 March 2007 16:44 |
sebastian
Messages: 3 Registered: March 2007
|
Junior Member |
|
|
Hi,
first of all: I'm new to OpenVZ and it well may be that i overlooked some obvious thing addressing my issue. But i searched the forum and the wiki but didn't found a concrete answer. So sorry if this is a typical newbie question.
I've set up some VE's in a Debian Etch HN (It's a VMWare-Machine for testing purposes). I'm using the VENET approach for networking (because of security concerns) and so far it's working fine. The VE's can access the internet and DNAT works too, but: I've found no nice way to restrict networking access between the VE's. I'm currently thinking of the following setup on the HN:
General Purpose VE's
- Database Server
- MTA
- DNS
- APT-Proxy
User VE's
- User VE 1
- ...
- User VE n
The User VE's should be able to access the general purpose VE's but should not be able to interconnect between them. Of course can i add matching firewall entries to all VE's but this seems like a classical case for building two networks. My problem is: I found no way to add netmasks or something similar through vzctl. What approach would you recommend in such a szenario?
Thanks very much in advance,
Sebastian
[Updated on: Tue, 06 March 2007 08:08] by Moderator Report message to a moderator
|
|
|
|
|
|
Re: *CLOSED* Good way to isolate VE networks. [message #11489 is a reply to message #11483] |
Sun, 25 March 2007 16:49 |
sebastian
Messages: 3 Registered: March 2007
|
Junior Member |
|
|
Hi Craig,
first of all: I got something working but only tested the theoretical Setup on a VMWare machine because i'm waiting for Debian etch to be released. This was more like a case study. I have not verified it for production use (since i'm not an iptables/firewall expert). So please don't be disappointed if this is not what you expected.
The network is as follows:
I use the network 10.10.10.0/8 for the internal machines. I access between those machines and access from those machines to e.g. the firewall and the internet is forbidden via policies. Certain machines are then granted to perform special operations using rules. This setup may be not perfect but i will fine tune it later when i do some real testing and prepare it for production.
I used shorewall for my setup but since it is only a nice interface for iptables you don't need to use it.
I configured three zones the "net" (Internet/LAN) the "fw" (default zone for the firewall(HN)) and "int" (The network for the VEs).
/etc/shorewall/zones:
#ZONE TYPE OPTIONS IN OUT
# OPTIONS OPTIONS
fw firewall
net ipv4
int ipv4
#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE
The "routeback" option is important! You can add more options to customize the setup.
/etc/shorewall/interfaces:
#ZONE INTERFACE BROADCAST OPTIONS
net eth0 detect proxyarp
int venet0 detect routeback
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE
/etc/shorewall/policy:
#SOURCE DEST POLICY LOG LIMIT:BURST
# LEVEL
fw int ACCEPT
fw net ACCEPT
#int net ACCEPT
int int DROP info
all all DROP info
#LAST LINE -- DO NOT REMOVE
I forward some ports to special VEs and allow certain machines to use services on other machines (e.g. DNS and apt-proxy).
/etc/shorewall/rules (This is really dirty but as i said this is nothing used for production)
DNAT net int:10.10.10.23 tcp 80
DNAT net int:10.10.10.24 tcp 53
DNAT net int:10.10.10.24 udp 53
ACCEPT int int:10.10.10.22 icmp
ACCEPT int int:10.10.10.24 tcp 53
ACCEPT int int:10.10.10.24 udp 53
ACCEPT int net icmp
ACCEPT int int:10.10.10.24 tcp 53
ACCEPT int int:10.10.10.24 udp 53
ACCEPT int net icmp
ACCEPT int fw tcp 9999
ACCEPT int fw udp 9999
ACCEPT int:10.10.10.24 net udp 53
ACCEPT int:10.10.10.24 net tcp 53
Then i use masquerading to let special machines access the internet (e.g. the internal apt-proxy and the dns)
/etc/shorewall/masq:
#INTERFACE SUBNET ADDRESS PROTO PORT(S) IPSEC
eth0 10.10.10.0/8
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE
If something doesn't work as expected you can of course contact me again. I had some problems implementing the setup so far and haven't had the time to polish it up. I'm looking forward to hearing from you.
best regards
Sebastian
|
|
|