of_topology cannot get bidirectional links between host and switch

[xiangq27]

I ran a simple mininet topology: h1--s1--s2--h2, let h1 ping h2 and then h2 ping h1. Both way work. Then I use the API provided by of_topology to get all the links. However, I notice that only 4 links are discovered, i.e., h1->s1, s1->s2, s2->s1 and s2->h2. The other two links s1->h1 and h2->s2 are not captured. Wonder if this was noticed before?

[xiangq27]

Update:

I report the wrong observation. The links returned are s1->h1, s1->s2, s2->s1 and s2->h2. And I think I found the cause in the following snipped in of_topology/main.py:

103 if endpoint in switches_mac_address:
104 continue
105
106 link = {'source': interface.id,
107 'target': endpoint.value,
108 'type': 'link'}
109 host = {"type": 'host',
110 "id": endpoint.value,
111 "name": endpoint.value,
112 "mac": endpoint.value}
113 if host not in nodes:
114 nodes.append(host)
115 if not interface.is_link_between_switches():
116 links.append(link)

When adding the link between host and a switch interface, only one link (switch intercace, hsot) is added, where the other direction should be added, too.

Comments?

[xiangq27]

Update:

I created a pull request (#307) to fix this issue. Please comment and let me know. Thank you very much.

[renanrodrigo]

Hello @xiangq27 ,
First of all, thanks for your collaboration.
Due to the holiday this weekend, the team will be able to send you proper feedback only next monday.
Besides that, we are working on a new version of the topology NApp, which shall be released soon.