topic Why the flow table will lost when the switch reboot? in Software Defined Networking

Why the flow table will lost when the switch reboot?

Yuanxiance — Thu, 21 Aug 2014 02:56:26 GMT

I used the switch HP2920,VAN SDN controller v2.0.I have added flow tables in the RSdoc API and we can see the flow tables in the CLI menu.But when I reboot the switch,the flow tables will lost.How to save the flow table in the switch.

Re: Why the flow table will lost when the switch reboot?

sepbot — Fri, 22 Aug 2014 05:23:50 GMT

If your flows are stored in software / RAM they will be lost after power is cut off since RAM is volatile memory and requires power to maintain any information.

Re: Why the flow table will lost when the switch reboot?

Yuanxiance — Fri, 22 Aug 2014 06:15:40 GMT

So I must add flow tables every time when I reboot the switch?How to get my flows stored in the switch as long as I don't delete it?

Re: Why the flow table will lost when the switch reboot?

sdnindia — Thu, 11 Sep 2014 18:26:43 GMT

Hello Yuanxiance,

The openflow entries are transient(Lives in the TCAM and RAM) and is not saved with the configuration and is thus lost when the switch is rebooted.
The Openflow application should reprogram the flows once the DPID comes back up.

Thanks,
HP SDN Team