Connectivity issues with microovn

[Giuseppe Petralia]

When creating a new LXD in a microcloud running microovn I am experiencing connectivity issue.

Snap version:
microovn 0+git.45624d8 106 latest/edge canonical✓ held

I have an existing LXD with IP: 172.16.0.4 on machine1

I create a new LXD with IP: 172.16.0.12 on machine3

First attempt to ssh to the LXD timeout, from second attempt it always works.

Tcpdumping on the hosts I see that on first attempt packets go out from veth of 172.16.0.4 but then I can't see them anywhere.

I tried on genev_sys_6081 on machine1 and on destination veth and genev_sys_6081 on machine3

Nothing is seen.

```
$ juju ssh 39
ERROR cannot connect to any address: [172.16.0.12:22 172.16.8.7:22]
```

Source Veth
```
root@machine1:~# tcpdump -enli vethe2f2c7c6 host 172.16.0.12 and port 22
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on vethe2f2c7c6, link-type EN10MB (Ethernet), snapshot length 262144 bytes
11:28:16.396425 00:16:3e:5d:f2:3e > 00:16:3e:b8:d1:2a, ethertype IPv4 (0x0800), length 74: 172.16.0.4.56508 > 172.16.0.12.22: Flags [S], seq 237990207, win 64240, options [mss 1460,sackOK,TS val 1551398338 ecr 0,nop,wscale 7], length 0
11:28:17.407207 00:16:3e:5d:f2:3e > 00:16:3e:b8:d1:2a, ethertype IPv4 (0x0800), length 74: 172.16.0.4.56636 > 172.16.0.12.22: Flags [S], seq 376664826, win 64240, options [mss 1460,sackOK,TS val 1551399349 ecr 0,nop,wscale 7], length 0
11:28:18.426219 00:16:3e:5d:f2:3e > 00:16:3e:b8:d1:2a, ethertype IPv4 (0x0800), length 74: 172.16.0.4.56642 > 172.16.0.12.22: Flags [S], seq 4253269441, win 64240, options [mss 1460,sackOK,TS val 1551400368 ecr 0,nop,wscale 7], length 0
11:28:19.436436 00:16:3e:5d:f2:3e > 00:16:3e:b8:d1:2a, ethertype IPv4 (0x0800), length 74: 172.16.0.4.56644 > 172.16.0.12.22: Flags [S], seq 2518808055, win 64240, options [mss 1460,sackOK,TS val 1551401378 ecr 0,nop,wscale 7], length 0
11:28:20.446859 00:16:3e:5d:f2:3e > 00:16:3e:b8:d1:2a, ethertype IPv4 (0x0800), length 74: 172.16.0.4.56654 > 172.16.0.12.22: Flags [S], seq 2804638595, win 64240, options [mss 1460,sackOK,TS val 1551402389 ecr 0,nop,wscale 7], length 0
```

Source genev_sys_6081
```
root@machine1:~# tcpdump -enli genev_sys_6081 host 172.16.0.12 and port 22
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on genev_sys_6081, link-type EN10MB (Ethernet), snapshot length 262144 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
```

Destination veth
```
root@machine3:~# tcpdump -enli vethf9598f1d host 172.16.0.4 and port 22
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on vethf9598f1d, link-type EN10MB (Ethernet), snapshot length 262144 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
```

Destination genev_sys_6081
```
root@machine3:~# tcpdump -enli genev_sys_6081 host 172.16.0.4 and port 22
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on genev_sys_6081, link-type EN10MB (Ethernet), snapshot length 262144 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
```

From second attempt on I see packets on all the interfaces mentioned above

```
$ juju ssh 39 "hostname"
juju-25c8b6-39
Connection to 172.16.0.12 closed.
```

[Frode Nordahl (fnordahl)]

Hello, Giuseppe,

Thank you for taking the time to report this bug.

I just tried this in a pristine environment and I cannot reproduce the issue.

I'm using these snap versions:
juju 3.1.6-484909e 24390 latest/edge canonical✓ -
lxd git-07070ec 25587 latest/edge canonical✓ -
microcloud 0+git.091ee78 540 latest/edge canonical✓ -
microovn 22.03.2+snap4a6fea39cd 244 22.03/stable canonical✓ -

Are you still seeing this issue?

[Launchpad Janitor (janitor)]

[Expired for microovn because there has been no activity for 60 days.]