DHCP Cleanup after VM destroy

[Syed Ahmed <sa...@cloudops.com>]

Hi All,

I was investigating an issue where we had a problem with DNS where, even
after deleting the VM, the DNS still resolved to an IP address. Going
through the code, I found out that there is no functionality that exisits
currently that cleans up DHCP entries. When you destroy a VM and create
another VM with the same name, there are some race conditions that lead to
old IPs being used for resolution.

Past issues [1,2] have pointed out to the same problem but I could not find
a fix that addresses them. I'm gong to work on a fix right now. If someone
has more info or has already fixed it. I would be delighted if you could
share that.

Thanks,
-Syed

[1] https://issues.apache.org/jira/browse/CLOUDSTACK-7974
[2] https://issues.apache.org/jira/browse/CLOUDSTACK-8060

Re: DHCP Cleanup after VM destroy

[Jayapal Uradi <ja...@accelerite.com>]

Hi Syed,

Reminding you the cases so that do don’t miss 2 and 3.

1. Deleting vm corresponding entry from the VR when VM is deleted
2. When VR is stopped, deleted a VM and started VR.
3. When VR is stopped, the last VM is deleted.

Thanks,
Jayapal

> On Oct 20, 2017, at 8:41 PM, Syed Ahmed <sa...@cloudops.com> wrote:
> 
> Hi All,
> 
> I was investigating an issue where we had a problem with DNS where, even
> after deleting the VM, the DNS still resolved to an IP address. Going
> through the code, I found out that there is no functionality that exisits
> currently that cleans up DHCP entries. When you destroy a VM and create
> another VM with the same name, there are some race conditions that lead to
> old IPs being used for resolution.
> 
> Past issues [1,2] have pointed out to the same problem but I could not find
> a fix that addresses them. I'm gong to work on a fix right now. If someone
> has more info or has already fixed it. I would be delighted if you could
> share that.
> 
> Thanks,
> -Syed
> 
> [1] https://issues.apache.org/jira/browse/CLOUDSTACK-7974
> [2] https://issues.apache.org/jira/browse/CLOUDSTACK-8060

DISCLAIMER
==========
This e-mail may contain privileged and confidential information which is the property of Accelerite, a Persistent Systems business. It is intended only for the use of the individual or entity to which it is addressed. If you are not the intended recipient, you are not authorized to read, retain, copy, print, distribute or use this message. If you have received this communication in error, please notify the sender and delete all copies of this message. Accelerite, a Persistent Systems business does not accept any liability for virus infected mails.