Network artifacts remains on CC after stop


What happens on the Cluster Controller (CC) ?

You have your cloud in MANAGED networking mode, so to summarize what this mode does : 

- When you create an instance in a security group, it will

-- Define an IP range for the security group

-- A VLAN to be used in order to provide L2 protection

-- A brige on both CC and NC to communicate, connected to the VLAN interface


Help ! I have an issue

It may happen that you have to troubleshoot a networking issue, so you basically see all the interfaces Eucalyptus has created. As you want to isolate different elements that may create the problem, you are going to stop the CC.


Looking at the system status now the CC service is stopped, you will look at the usual stuff : iptables, ifconfig, vconfig and brctl. 

You still see a lot of artifacts remaining on the CC. You may wonder why all these are still here.

So next step, as a sysadmin, you are going to take is to remove all these elements, manually.

Nothing bad in there, but actually useless.


Why all these elements remain in place ?

In Eucalyptus, we care about recovery and performances. After years of tests and developments, we realized that it was heavy for the system to build / delete / rebuild all the interfaces your cloud needs to run.

So from there, do not panic, these remaining elements are there your good.

In addition to that, most of these elements are actually disabled : not used, nor involved in any networking stuff. 


How "unused" elements appeart ? What is the cause of that ?

If you are using a lot of security groups, which is good to separate your network applications from the others, you will have 1 couple {vlan/bridge} created and associated to this security group.

So for example, while your are using Eucalyptus for a first application, you will do all the SGs you need. Then, once it is ready, you upload your recipe to AWS and jump to another project, once more on Eucalyptus.

You will create a whole set of new security groups, for this new application. And so will remain the others, because you may use them again later.


I want to remove all unused anyway, because I have to troubleshoot and all these elements, it is too much !

It is pretty easy to remove all the artifacts (bridges and vlans) which remain in place.

brctl delbr <brid>

vconfig rem <interface>.<vlanid>

But all these unused elements are kept in memory, locally on the CC. So if you restart the CC, you will see once more the activated artifacts (used by your cloud right now) and the others. To definitely clean this, remove files under /var/lib/eucalyptus/CC (on the CC). These files are going to be rebuilt using only the useful elements.



If artifacts are still there, this is normal. Don't panic


Have more questions? Submit a request


Powered by Zendesk