[ovs-discuss] In-band management

Luís Santos luis.eduardo.santos at gmail.com
Wed Nov 26 12:50:20 UTC 2014

Dear all,

I have the following very basic topology:

ovs1 ---- ovs2 ---- controller.

According to the DESIGN.txt file (from the OvS source tree), it seems that
the OvS switch is able to handle such scenario regarding the "in-band
management" needs:
" ...  - Between Switch and Remote.  This switch is between another switch
and the remote, and we want to allow the other switch's traffic through.
This uses rules (d), (e), (h), and (i).  It uses (b) and (c) indirectly in
order to know the MAC address for rules (d) and (e).  Note that DHCP for
the other switch will not work unless an OpenFlow controller explicitly
lets this switch pass the traffic.

However what I'm being observing is a different behavior. After programming
ovs2 with the controller's IP, this switch presents the following flow
entries (that I sort by priority and number for reference):
1) duration=3s, n_packets=3, n_bytes=162,
2) duration=3s, n_packets=3, n_bytes=222,
5) duration=3s, n_packets=0, n_bytes=0,
8) duration=3s, n_packets=0, n_bytes=0,
6) duration=2s, n_packets=0, n_bytes=0,
4) duration=2s, n_packets=0, n_bytes=0,
7) duration=3s, n_packets=1, n_bytes=42,
3) duration=3s, n_packets=1, n_bytes=42,
9) duration=3s, n_packets=0, n_bytes=0,

After that I program ovs1 with the same controller's IP address ovs2 is
using. I capture ARP.Requests sent by ovs1 and reaching ovs2. OvS2 however
is not forwarding them.  Is it the expected behavior? It seems that the
ARP.Request sent by ovs1 (looking for the MAC of the controller
should match flow entry 8 but the packet counter of this flow entry remains
zero. After more experiments I found out that such traffic (ARP.Req) is
matching the following entry:
table_id=254, duration=1409s, n_packets=205, n_bytes=17092,

Is this an OvS bug? Help me understanding this behavior, please. Where are
the table 254 usage documented?

Best regards,
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://openvswitch.org/pipermail/ovs-discuss/attachments/20141126/ecf1115e/attachment-0002.html>

More information about the discuss mailing list