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Re: Understanding Integration Bridge and MACs

 

On Mon, May 14, 2012 at 3:19 PM, Salman Malik <salmanmk@xxxxxxxx> wrote:

>  In addition to the mail that follows, I am having some problem with
> quantum networks as well. When I create a network using :
>
> sudo nova-manage network create --label=$tenant0
> --fixed_range_v4=$iprange0 --project_id=$tenant0
>
> I can see the network using both "quantum list_nets $tenant0" and
> "nova-manage network list", but when I delete the network using "quantum
> delete_net $tenant0 $netID", the nova-manage network list still shows the
> network and when I try to use the same CIDR for another network,I get an
> error saying CIDR already in use. Shouldn't deleting "quantum list_nets"
> and "nova-manage network list" be consistent with each other ?
>

In Essex, when using Nova all Quantum network creation and deletion must
occur using nova-manage.  This is because we store the IP address
management data associated with a network is stored in the Nova database.
 As Yong mentioned, in Folsom we are storing IP address management data in
Quantum itself, in which case network creation can happen directly via the
Quantum API and Nova VMs will still be able to get IPs.

Dan



>
>
>
>
> ------------------------------
> From: salmanmk@xxxxxxxx
> To: openstack@xxxxxxxxxxxxxxxxxxx
> Subject: Understanding Integration Bridge and MACs
> Date: Sun, 13 May 2012 19:42:14 -0500
>
>
>  Hi Dan and Others,
>
> I am trying to understand the actions taken by Ryu when the new instance
> sends DHCP discover message to dnsmasq. When I launch new instannce it
> keeps on sending discover messages and controller keeps on dropping these
> messages. But looking at the traffic I couldn't exactly map which MAC
> address belonged to which entity. Can someone help me with my understanding
> of the MAC addresses. Using ifconfig , "ovs-ofctl show br-int" and
> "ovs-ofctl snoop br-int" (output shown after MAC addresses), I know exactly
> about some MAC addresses and can't figure out some of them:
>
> Interfaces              |        HWAddress          |        IP-addr
>
> ---------------------------------------------------------------------------------------------
> eth0                        |        08:00:27:7a:ff:65    |    10.0.3.15
> eth1                        |        08:00:27:16:d5:09  |
> 10.0.0.10             <========plugged into br-int
> gw-82bd3a73-dc    |        fa:16:3e:49:57:1b  |    10.0.0.1
> <========plugged into br-int (this is the --listen-address of my two
> dnsmasqs)
> br-int                       |        08:00:27:16:d5:09 |
>                 <========why doesn't bridge have no IP ?
> new-instance          |        *02:d8:47:48:35:26*  <====== MAC address
> of newly launched instance? (see output below)
>
> *Unkown*                 |        *fa:16:3e:5e:02:17   *<======Seemingly
> unknown MAC address(which is related to the new instance?)
> Unkown                  |        *33:33:00:00:00:16**   *<====== MAC
> address related to multicast ?
>
>
> Questions:
>
> 1. What is gw-82bd3a73-dc interface ?
> 2. I am kind of unsure why br-int is so useful?
> 3. Why doesn't br-int don't have any IP address?
> 4. Why do we need to plugin a compute node's interface to br-int? (so that
> guest instances on remote host can communicate with each other?)
> 5. What is the relationship b/w *02:d8:47:48:35:26 and **fa:16:3e:5e:02:17
> *MAC addresses in the following output?
>
> =====================
> Output of : ovs-ofctl snoop br-int
> =====================
> OFPT_ECHO_REQUEST (xid=0x0): 0 bytes of payload
> OFPT_ECHO_REPLY (xid=0x0): 0 bytes of payload
> OFPT_PORT_STATUS (xid=0x0): ADD: 7(tap76127847-b1): addr:*
> 02:d8:47:48:35:26*
>      config:     0
>      state:      LINK_DOWN
>      current:    10MB-FD COPPER
> OFPT_FLOW_MOD (xid=0x491662da): DEL priority=0 buf:0x0 actions=drop
> OFPT_BARRIER_REQUEST (xid=0x491662db):
> OFPT_BARRIER_REPLY (xid=0x491662db):
> OFPT_PORT_STATUS (xid=0x0): MOD: 7(tap76127847-b1): addr:*
> 02:d8:47:48:35:26*
>      config:     0
>      state:      0
>      current:    10MB-FD COPPER
> OFPT_ECHO_REQUEST (xid=0x0): 0 bytes of payload
> OFPT_ECHO_REPLY (xid=0x0): 0 bytes of payload
> OFPT_PACKET_IN (xid=0x0): total_len=90 in_port=7 data_len=90
> buffer=0x00000167
> tunnel0:in_port0007:tci(0) macfa:16:3e:5e:02:17->33:33:00:00:00:16
> type86dd proto58 tos0 ipv6::->ff02::16 port143->0
> *fa:16:3e:5e:02:17 *> *33:33:00:00:00:16*, ethertype IPv6 (0x86dd),
> length 90: :: > ff02::16: HBH ICMP6, multicast listener report v2, 1 group
> record(s), length 28
> OFPT_PACKET_OUT (xid=0x491662dc): in_port=7 actions_len=0 actions=drop
> buffer=0x00000167
> OFPT_PACKET_IN (xid=0x0): total_len=322 in_port=7 data_len=128
> buffer=0x00000168
> tunnel0:in_port0007:tci(0) macfa:16:3e:5e:02:17->ff:ff:ff:ff:ff:ff
> type0800 proto17 tos0 ip0.0.0.0->255.255.255.255 port68->67
> *fa:16:3e:5e:02:17* > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length
> 128: truncated-ip - 194 bytes missing! 0.0.0.0.68 > 255.255.255.255.67:
> BOOTP/DHCP, Request from fa:16:3e:5e:02:17, length 280
> OFPT_PACKET_OUT (xid=0x491662dd): in_port=7 actions_len=0 actions=*drop*buffer=0x00000168
> OFPT_PACKET_IN (xid=0x0): total_len=78 in_port=7 data_len=78
> buffer=0x00000169
> *fa:16:3e:5e:02:17* > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length
> 128: truncated-ip - 194 bytes missing! 0.0.0.0.68 > 255.255.255.255.67:
> BOOTP/DHCP, Request from fa:16:3e:5e:02:17, length 280
> OFPT_PACKET_OUT (xid=0x491662e3): in_port=7 actions_len=0 actions=drop
> buffer=0x0000016e
> OFPT_PACKET_IN (xid=0x0): total_len=70 in_port=7 data_len=70
> buffer=0x0000016f
> tunnel0:in_port0007:tci(0) macfa:16:3e:5e:02:17->33:33:00:00:00:02
> type86dd proto58 tos0 ipv6fe80::f816:3eff:fe5e:217->ff02::2 port133->0
> fa:16:3e:5e:02:17 > 33:33:00:00:00:02, ethertype IPv6 (0x86dd), length 70:
> fe80::f816:3eff:fe5e:217 > ff02::2: ICMP6, router solicitation, length 16
> OFPT_PORT_STATUS (xid=0x0): MOD: 7(tap76127847-b1): addr:*
> 02:d8:47:48:35:26*
>      config:     0
>      state:      LINK_DOWN
>      current:    10MB-FD COPPER
> OFPT_PORT_STATUS (xid=0x0): DEL: 7(tap76127847-b1): addr:*
> 02:d8:47:48:35:26*
>      config:     0
>      state:      LINK_DOWN
>      current:    10MB-FD COPPER
> OFPT_FLOW_MOD (xid=0x491662e5): DEL priority=0,in_port=7 actions=drop
> OFPT_FLOW_MOD (xid=0x491662e6): DEL priority=0 actions=drop
> OFPT_BARRIER_REQUEST (xid=0x491662e7):
> OFPT_BARRIER_REPLY (xid=0x491662e7):
>
> Thanks!
> Salman
>
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>


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dan Wendlandt
Nicira, Inc: www.nicira.com
twitter: danwendlandt
~~~~~~~~~~~~~~~~~~~~~~~~~~~

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