Adding new volumes to an Ubuntu Lucid guest instance running under KVM hypervisor seems to not work automatically. The newly attached device is visible to the Ubuntu guest OS only after a reboot.
To replicate the issue…
- Create a Ubuntu Lucid guest instance on KVM
- Create a new data disk
- Attach the new data disk to the Ubuntu guest OS
- Run fdisk -l /dev/vdb on the Ubuntu KVM Guest OS. No disks found
shanu@ubuntu3:~$ sudo fdisk -l /dev/vdb|wc -l
- Reboot and run fdisk again. Disk is now available as /dev/vdb
shanu@ubuntu3:~$ sudo fdisk -l /dev/vdb
Disk /dev/vdb: 5368 MB, 5368709120 bytes
16 heads, 63 sectors/track, 10402 cylinders, total 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/vdb doesn't contain a valid partition table
The tests were performed on Apache CloudStack 4.2.0+CentOS 6.5 KVM hypervisor hosts and Ubuntu 12.04 Lucid as guest operating system.
The same steps work correctly on XenServer guest operating systems (tested on Ubuntu,Linux and FreeBSD) and CentOS guest on KVM. Since its working automatically without a reboot in CentOS/KVM, it didn’t seem to be a CloudStack issue per-se.
Continue reading “CloudStack Attach Volumes On Ubuntu Not Working on KVM”
A Shared Network in CloudStack can be used to assign public IPs to guest VM instances instead of internal private IPs. A Guest VM with a routable public IP is directly reachable from the Internet without using any NAT services. Services providers usually create a one or more shared networks with public subnets to provide VPS/shared hosting services for their customers. Please also see earlier post on CloudStack Shared Networks.
For guest instances which are on a VLAN based Isolated Network, the CloudStack managed virtual router (VR) provides NAT/SNAT and firewall services. Users can modify the Network ACLs directly from the CloudStack UI. Virtual routers however, cannot be used as firewall on shared networks as they are directly accessible from the Internet.
So what options are available to provide firewall services in shared networks?
Continue reading “CloudStack Advanced Zone With Security Groups”
Apache CloudStack works with a variety of hypervisors and a single CloudStack cloud deployment can have multiple hypervisors implementations. Some of the more popular hypervisors supported by CloudStack are Linux KVM, XenServer and VMware vSphere.
It is a generally perceived that the Cloud Management Platform (CloudStack) does magical things to support guest operating systems like Windows, Linux or BSD on the hypervisor hosts. In reality, CloudStack is just a consumer of the hypervisor’s capabilities. The ability of CloudStack to provision various guest operating systems is directly dependent on the hypervisor used.
Not all hypervisors are created equal and there-in lies the problem. Depending on the hypervisor vendor and the hypervisor version, the latest and greatest Operating System might have full, minimal or no support at all by the hypervisor.
As of CloudStack 4.2, the listOsTypes API returns the following list of Operating Systems as supported…
Continue reading “What Guest Operating Systems Does CloudStack Support?”