On Tue, Jul 24, 2012 at 02:24:53PM -0400, Sheng Yang wrote: > Yes. And the reason of recalculating the CIDR of network for > external devices because we allocate the CIDR based on VLAN, which > would be recycled after network shutdown. > > --Sheng
I have a question around this. Does the network not get re-implemented when the network is restarted? The restart process from the logs tells me that network shutdown happens and network rules are released, router destroyed and a new one spun up and all rules reapplied. But the VLAN was never released and the same one from before the restart was used. Perhaps this is just the case with regular VRs? Then, I tried with an external device (NetScaler in my case) and the dynamic CIDR as you mention is calculated based on VLAN. I launched a couple of guests in this network. Restarted the network (cleanup=true) and the new network came up with the same VLAN and consequently the same CIDR. It seems ideal that this happens. If a new VLAN and new CIDR came up on reimplement, would the guests not have to renew their DHCP configured IPs? These old IPs belong to an older CIDR/gateway. The new network might be in a completely different CIDR/gateway. Am I missing something? When network.gc runs however it releases the VLANs. But network.gc only happens in the absence of running guests. In this case DHCP is renewed next time the guest VMs start. So the network seems to change only in this case. -- Prasanna., > > -----Original Message----- > From: Alena Prokharchyk > Sent: Tuesday, July 24, 2012 9:51 AM > To: [email protected]; Sheng Yang > Subject: Re: will IP assigned to a guest VM(via DHCP) ever expiry or will > need renewal...? > > On 7/24/12 7:53 AM, "Ram Ganesh" <[email protected]> wrote: > > >Hi All, > > > >Would like to know if an IP assigned by CloudStack via its DHCP server > >to a guest VM will ever expire? Or is it ok to assume the IP will be > >assigned to a guest VM as long as it is not destroyed. We are exploring > >means to enhance our load balancer to support DHCP and once we acquire > >an IP we would assign it statically to the load balancer device. Please > >let me know > > > >Thanks, > >Ram > > > > > > > It will not expire in most of the cases - the IP will stick to Vm > for the entire lifecycle as the cidr for the network doesn't change > once its set usually. > > But if external device (Netscaler, Juniper SRX) is used as a > provider for the network, then the cidr for the network is > calculated dynamically every time the network gets > shutdown/re-implemented. As the CIDR changes, so do all the user > vms' ips. > > Sheng, please confirm. > > -Alena.
