Hi Koushik,
[ShapeBlue]<http://www.shapeblue.com> Rohit Yadav Software Architect , ShapeBlue d: | s: +44 203 603 0540<tel:|%20s:%20+44%20203%20603%200540> | m: +91 8826230892<tel:+91%208826230892> e: rohit.ya...@shapeblue.com | t: <mailto:rohit.ya...@shapeblue.com%20|%20t:> | w: www.shapeblue.com<http://www.shapeblue.com> a: 53 Chandos Place, Covent Garden London WC2N 4HS UK [cid:image6d46e0.png@6cbf0119.47b60f2c] Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue Services India LLP is a company incorporated in India and is operated under license from Shape Blue Ltd. Shape Blue Brasil Consultoria Ltda is a company incorporated in Brasil and is operated under license from Shape Blue Ltd. ShapeBlue SA Pty Ltd is a company registered by The Republic of South Africa and is traded under license from Shape Blue Ltd. ShapeBlue is a registered trademark. This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. On 03-Mar-2016, at 2:38 PM, Koushik Das <koushik....@accelerite.com<mailto:koushik....@accelerite.com>> wrote: Host maintenance is already there to address the use cases mentioned. What additional value would this feature add? Host maintenance and out-of-band power management are both different things, and don’t address the same use-cases. Also if it is just providing the IPMI based operations then it is only limited to the hosts already added to CS, what about new hosts not added in CS? What if host IP/name/password etc. which are already stored in CS needs to be changed? Limited to hypervisor hosts that have been already added in CloudStack. Nothing we can do about (hypervisor) hosts, CloudStack does not know of. The out-of-band management interface (such as iLo, iDRAC based) is a separate computer (BMC, https://en.wikipedia.org/wiki/Intelligent_Platform_Management_Interface#Baseboard_management_controller) with a separate NIC, power etc. it’s not same as the (hypervisor) host itself. Therefore, has its own IP address etc. If the out-of-band management credentials (ip, port, username, password) is changed then this information needs to be updated in CloudStack as well. If an admin wants to change the password of user for the out-of-band management interface for a (hypervisor) host, they can use the change oobm password API which will change the password on the BMC and also update this information in CloudStack. To understand out-of-band management related concepts, you can play with the ‘ipmisim’ tool that I created for this testing this feature: 1. pip install —upgrade ipmisim 2. Run ipmisim in a separate terminal 3. Run ipmitool to see the power status, issue some power commans: (osx users, do a brew install ipmitool; don’t use apple/bsd ipmitool) ipmitool -I lanplus -H localhost -p 9001 -R1 -U admin -P password chassis power status -v # by default server should report Off ipmitool -I lanplus -H localhost -p 9001 -R1 -U admin -P password chassis power on -v ipmitool -I lanplus -H localhost -p 9001 -R1 -U admin -P password chassis power status -v # see the server would report server is On now Some questions on use cases. * Restarting stalled/failed hosts [Koushik] How do you determine if a host stalled/failed? What happens if the host lost network connectivity intermittently? It depends, if you’re asking if this is done automatically — no, it’s a manual operation (for now, though could be useful if we want to do host HA and fencing in future). The admin can assess their situation, for example check the power state with this feature (which they normally would do by running ipmitool chassis power status command) and if the power state is On they can turn them On by issuing a power action (from UI/API). * Powering off under-utilised hosts [Koushik] What is the definition of "under-utilised" - no VMs or based on some resource threshold? It depends, the main idea is that you can execute a power operation. By 'Under-utilised hosts’ I mean to say hosts without any VMs on them. If there are some running VMs (HA and non-HA) what happens to them? Don’t understand what you’re trying to ask. I suppose bad things will happen to non-HA VMs if you turn off (hypervisor) hosts. * Powering on hosts for provisioning and to increase capacity (for hosts already provisioned) [Koushik] Again how do you power on new hosts not yet added to CS? For hosts already provisioned or added to CloudStack. * Allowing system administrators to see the current power state of the host [Koushik] When would the power state differ from the existing host state shown in CS? There can be certain corner scenarios when CS may not determine the host state conclusively (e.g. last host in cluster), but otherwise shouldn't it be the same? Power state can differ when you’re doing a power operation (such as on/off/reset etc) or say in case of a power outage. See the FSM for details. CloudStack won’t be able to determine the out-of-band management power state of a hypervisor host in case of (1) network connectivity issue when trying to connect to the BMC (the power state will be put in Unknown state, events issued), (2) the password/credentials are incorrect (alert will be issued, admins will get an email if enabled). Regards. Find out more about ShapeBlue and our range of CloudStack related services: IaaS Cloud Design & Build<http://shapeblue.com/iaas-cloud-design-and-build//> | CSForge – rapid IaaS deployment framework<http://shapeblue.com/csforge/> CloudStack Consulting<http://shapeblue.com/cloudstack-consultancy/> | CloudStack Software Engineering<http://shapeblue.com/cloudstack-software-engineering/> CloudStack Infrastructure Support<http://shapeblue.com/cloudstack-infrastructure-support/> | CloudStack Bootcamp Training Courses<http://shapeblue.com/cloudstack-training/>
