The Technology Chronicle

While trying to install OpenStack icehouse, faced an issue with nova-api service.It was not getting started. The following error was coming up in the Nova-api log Command: sudo nova-rootwrap /etc/nova/rootwrap.conf iptables-save -c Exit code: 1 .......  nova Stdout: '' 2014-10-17 07:21:08.058 27270 TRACE nova Stderr: 'Traceback (most recent call last):\n  File "/usr/bin/nova-rootwrap", line 6, in <module>\n    from oslo.rootwrap.cmd import main\nImportError: No module named rootwrap.cmd\n' Problem was with one of the oslo.rootwrap module. It was broken Solution is to upgrade the module using pip   #pip install oslo.rootwrap --upgrade

In OpenStack, by default users who are members of a  tenant can delete all instances in that tenant, even if it is spinned up by other users. If you want to restrict that, you  need to tweak the nova policy file  ie /etc/nova/policy.json Add the following lines in the file:     "admin_or_user":"is_admin:True or user_id:%(user_id)s",     "compute:delete":"rule:admin_or_user", Make the same changes in the /etc/openstack-dashboard/nova_policy.json file also Now restart the openstack-nova-api service Now user will be able to delete only those instances spinned up by them. Admin users will be able to delete all instances

Creating Yaml templates that assign floating IPs to your instances being spawned can be a bit tricky.Let us look at a scenario where we need to spin up a VM, assign a floating IP from a pool and make reference to this floating IP in your userdata as well. We will make use of the network ID of the internal and external network, as well as the Subnet ID of the internal network The logical workflow is as follows:   Create a port resource using internal network and internal subnet IDs Create a floating IP resource , referring to the external network ID   Associate the floating IP to the port   In the server resource being created, associate the port resource   Now we will see how this can be implemented using both HOT and AWS template formats

Recently a Ceilometer proxy for Zabbix was released by OneSource. This proxy will pull all the instance information from OpenStack and populate it in Zabbix The source code can be downloaded from here: https://github.com/OneSourceConsult/ZabbixCeilometer-Proxy The basic prerequisites for the server where the proxy is running is Python and Pika library. Also there should be network connectivity from the proxy machine to your OpenStack installation.

Zabbix can be a tough cookie to crack!! And if you are planning to monitor Openstack using Zabbix, there is lot of additional work to be done .More so, if you want to go the agentless way, ie using SNMP So, here we go.I am using Ubuntu 12.04 OS, both for my Zabbix server as well as openstack nodes First you need to install the following packages using apt-get in the machine being monitored ie the openstack node

1. List the keystone tenants and search for the required tenant keystone tenant-list |grep <tenantname>  Note the id of the tenant being displayed. You need to use this id in the next command 2. Get quota details of the tenant using the following command nova-manage project quota <tenantid>

Issue:  All instances in openstack will be in paused node. You will not be able to create new instances or switch on any of the paused instances Reason:  Most often the reason will be lack of disk space in your compute node. By default the instances are created in the /var/lib/nova/instances folder of the compute node. This location is defined by the parameter "instances_path" in nova.conf of the  compute node. If your "/" partition is running out of disk space, then you cannot perform any instance related operations Solution:  Change the "instances_path" location to a different location. Ideally you could attach an additional disk and mount it to a directory and update the directory path in the "instance_path" variable.   Problem arises when you already have a number of instances  in the previous folder. You should move them over to the new location.  Also you should set the group and ownership of the new instances folder to ...