[ovs-discuss] [BUG] multi-/broadcast counter, sFlow

Peter Phaal peter.phaal at inmon.com
Tue Apr 24 18:19:56 UTC 2012


Chris,

The sFlow standard indicates unknown values as follows:

   The following values should be used for fields that are
   unknown (unless otherwise indicated in the structure
   definitions).
      - Unknown integer value. Use a value of 0 to indicate that
        a value is unknown.
      - Unknown counter. Use the maximum counter value to indicate
        that the counter is not available. Within any given sFlow
        session a particular counter must be always available, or
        always unavailable. An available counter may temporarily
        have the max value just before it rolls to zero. This is
        permitted.
      - Unknown string. Use the zero length empty string.

See http://sflow.org/sflow_version_5.txt, page 34.

The Open vSwitch exports the interface counters that are maintained by the Linux kernel (see /proc/net/dev). The ifInBroadcastPkts, ifInUnknownProtos, ifOutMulticastPkts, ifOutBroadcastPkts counters aren't available and are marked as unknown in the sFlow counter structure. 

Peter

On Apr 24, 2012, at 6:29 AM, Christoffer Loeffler wrote:

> Hello,
> 
> I ran in a curious measurement when I looked at sFlowTool and sFlowTrend
> numbers.
> 
> Several counters display 4,294,967,295. These are ifInBroadcastPkts,
> ifInUnknownProtos, ifOutMulticastPkts, ifOutBroadcastPkts.
> 
> My setup uses the software at [1] and I start it with [2]. For enabling
> multicasting I run the following command [0] in each lxc-shell
> [0] route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0
> 
> Is there a possible workaround I can use to reset the sFlow database
> entries to numbers which are more useable? Looks like this uint(?) was set
> to -1..
> 
> Chris
> 
> 
> [1]Installed Software:
> openvswitch-1.4.0, sflowtool-3.25, Ubuntu 11.10 Kernel 3.0.0-12 in
> VirtualBox, connecting lxc-containers via brctl compatiblity mode.
> 
> [2]Reproduce via:
> 
> cd ~/openvswitch-1.4.0 && sudo -s
> rmmod bridge
> insmod ./datapath/linux/openvswitch_mod.ko
> insmod ./datapath/linux/brcompat_mod.ko
> ovsdb-tool create /usr/local/etc/openvswitch/conf.db
> vswitchd/vswitch.ovsschema
> ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock
> --remote=db:Open_vSwitch,manager_options --pidfile --detach
> ovs-vsctl --no-wait init
> ovs-vswitchd --pidfile --detach
> ovs-brcompatd --pidfile --detach
> brctl addbr br0
> ovs-vsctl -- --id=@s create sFlow agent=lo target=\"127.0.0.1:6343\"
> header=128 sampling=64 polling=1 -- set Bridge br0 sflow=@s
> 
> lxc.conf:
>> lxc.utsname = one
>> lxc.network.type = veth
>> lxc.network.flags = up
>> lxc.network.link = br0
>> lxc.network.ipv4 = 10.0.0.1/24
> 
> mkdir /cgroup
> mount -t cgroup cgroup /cgroup
> lxc-create -n one -f lxc.conf
> lxc-start -n /bin/bash
> 
> sflowtool
> 
> _______________________________________________
> discuss mailing list
> discuss at openvswitch.org
> http://openvswitch.org/mailman/listinfo/discuss

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://openvswitch.org/pipermail/ovs-discuss/attachments/20120424/8f4ed82f/attachment-0001.html>


More information about the discuss mailing list