Re: [patch v1 00/12] IPVS: SIP Persistence Engine

[Simon Horman <horms@verge.net.au>]

On Sun, Aug 22, 2010 at 09:44:57PM +0900, Simon Horman wrote:
> This patch series adds load-balancing of UDP SIP based on Call-ID to
> IPVS as well as a frame-work for extending IPVS to handle alternate
> persistence requirements.
> 
> REVISIONS
> 
> This is "patch v1" of this series, which addresses a few minor problems, as
> annotated on a per-patch basis, since the initial "rfc" posting. Internally
> there were 4 rfc versions, 0.1, 0.2, 0.3 and 0.4, some of the notes for
> some of the patches reflect those versions.
> 
> OVERVIEW
> 
> The approach that I have taken is what I call persistence engines.
> The basic idea being that you can provide a module to LVS that alters
> the way that it handles connection templates, which are at the core
> of persistence. In particular, an additional key can be added, and
> any of the normal IP address, port and protocol information can either
> be used or ignored.
> 
> In the case of the SIP persistence engine, the only persistence engine, all
> the keys used by the default persistence behaviour are used and the callid
> is added as an extra key. I originally intended to ignore the cip, but this
> can optionally be done by setting the persistence mask (-M) to 0.0.0.0
> while allowing the flexibility of other mask values.
> 
> It is envisaged that the SIP persistence engine will be used in conjunction
> with one-packet scheduling. I'm interested to hear if that doesn't fit your
> needs.
> 
> 
> CONFIGURATION
> 
> A persistence engine is associated with a virtual service
> (as are schedulers). I have added the --pe option to the
> ivpsadm -A and -E commands to allow the persistence engine
> of a virtual service to be added, changed, or deleted.
> 
> e.g. ipvsadm -A -u 10.4.3.192:5060 -p 60 -M 0.0.0.0 -o --pe sip
> 
> There are no other configuration parameters at this time.
> 
> 
> RUNNING
> 
> When a connection template is created, if its virtual service
> has a persistence engine, then the persistence engine can add
> an extra key to the connection template. For the SIP module this
> is the callid. More generically, it is known as "pe data". And
> both the name of the persistence engine, "pe name", and "pe data"
> can be viewed in /proc/net/ip_vs_conn and by passing the
> --persistent-conn option to ipvsadm -Lc.
> 
> e.g.
> # ipvsadm -Lcn --persistent-conn
> UDP 00:38  UDP         10.4.3.0:0         10.4.3.192:5060    127.0.0.1:5060 sip 193373839
> 
> Here we see a single persistence template (cport is 0), which has been
> handled by the sip persistence engine. The pe data (callid) is 193373839.
> 
> In the case where the persistence engine can't match a packet for some
> reason, the connection will fall back to the normal persistence handling.
> This seems reasonable, as that if the packet ought to be dropped, iptables
> could be used.
> 
> A limited amount of debugging information has been added which
> can be enabled using a value of 9 or greater in
> /proc/sys/net/ipv4/vs/debug_level
> 
> CODE AVAILABILITY
> 
> The kernel patches (13) are available in git as the pe-0.4 branch of
> git://git.kernel.org/pub/scm/linux/kernel/git/horms/lvs-test-2.6.git
> 
> The ipvsadm patches (2) are available in git as the pe-0.4 branch of
> git://github.com/horms/ipvsadm-test.git

pe-0.4 should read pe-1 above (x2).
pe-0.4 is an older revision.

> I will post the ipvsadm patches separately