From: Jacques Gelinas (jack_at_solucorp.qc.ca)
Date: Wed 20 Mar 2002 - 20:49:00 GMT
1.1. chbind: broadcast address
chbind accepts the --bcast option. It is supporting the new
set_ipv4root which requires an IP number and a broadcast address.
If you only specify the --ip option with a device, the broadcast
address of the device is used. This is used namely in the
/usr/sbin/chbind --ip eth0 /bin/sh
the new chbind works on older kernel. The broadcast address is simply
1.2. kernel 2.4.18ctx-9: set_ipv4root changed
This new kernel enhances set_ipv4root a bit. This is not the multi-ip
support yet though. This kernel allows application relying on
broadcast to work in vservers. The trick is to assigned both an IP
number and a broadcast address to a vserver. The socket handling for
UDP was modified a little (one line in net/ipv4/udp.c) so an incoming
packet is processed if it matched the vserver IP or the vserver
There is no configuration changed to take advantage of that. You need
the new kernel and vserver-0.14. Stuff like samba (which was already
working in most cases) are now working completely. Even dhcpd works
inside a vserver (see the FAQ though).
So the set_ipv4root was changed, but the kernel sports a syscall
versioning system and vserver-0.14 supports it. So vserver-0.14 works
with any "ctx" kernel. The new kernel works also with older vserver
utilities except the vserver broadcast address will be improperly
1.3. vfiles: new utility
The vfiles utility is used to extract the list of non-unifiable files
in a vserver. The utility works like this
/usr/sbin/vfiles reference-server server
Using the output of this command, one may archive only the relevant
part of a vserver. You can use this to move a vserver from one server
to another. Only move few megs. On the target server, use vunify to
fill the missing files. You must have a identical reference server on
the target server though.
Anyway, this is general purpose. Life may tell us if this is really
1.4. vps reworked
vps was reworked a little. The previous version was not working on
some distro. Test it out.
1.5. vserver configuration file
There are two new optional entries in /etc/vservers/*.conf:
+ IPROOTMASK: This is the netmask used to configure the IP alias. By
default, it uses the netmask of the IPROOTDEV device.
+ IPROOTBCAST: This is the broadcast address used to configure the IP
alias. Again, it uses the IPROOTDEV device settings by default.
You generally do not need to assign those fields. Just upgrading to
vserver 0.14 and restarting your vserver and the IP alias will be
configure. This was an issue for some service (as seen on the
mailing list). Prior version were always setting the netmask to
1.6. vserver-stat and dynamic system calls
The utility was using fixed system call numbers unlike the other
vserver utilities. Fixed!
1.7. v_xxxx services enhancements
/etc/init.d/v_sendmail was added to the list. By default each v_xxxx
service perform a chbind on the main eth0 address. For each service,
you can setup a file called /etc/vservices/service.conf (one per
service). In that file, you can specify a different IP or device.
The extra configuration file is optional.
Jacques Gelinas <jack_at_solucorp.qc.ca>
vserver: run general purpose virtual servers on one box, full speed!