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14

The outcome you want to achieve, and the manner in which you have decided to do it, are very different things. To be blunt, what you want to implement is a bad idea, and if you can somehow manage to make it work, it won't work for very long (or very well). What makes this question difficult to answer is that you've leapt straight to the implementation, and ...


11

The reason you're frustrated is because you're trying to do something that you shouldn't be doing. You say If anyone is now saying, “wait, what about a SAN or a NAS for the file servers?”, well too bad.` You're right. Too bad for you. What you're trying to do cannot work. A cluster disk must be the same disk shared amongst cluster members. You can't ...


8

The physical cluster makes your virtual hardware highly available, i.e. failures of a physical server don't affect any given virtual machine. However, the virtual machine itself can still fail (e.g. OS crashing, someone shutting down the virtual server, etc.), so the service running on top of the virtual machine may still fail at some point (although it's ...


6

Being that it's a proprietary product I don't think you're going to binary-level analysis of the protocol or even flow diagrams, but I think you can glean some helpful information from: The Design and Architecture of the Microsoft Cluster Service - This paper, co-authored by one of my CompSci heroes Jim Gray (RIP, Jim), published in the 1998 IEEE ...


6

The space actually used by a quorum disk amounts at most to a few kilobytes, not even megabytes. There is really no reason at all to go above the suggested size. That said, creating a LUN and a NTFS volume of a few megabytes in size would be impractical for several reasons; the most common size for quorum disks in my experience is 1 GB, and even that is ...


6

Enabling Conflict detection (which is not enabled by default) will probably resolve this.


6

First, you need to define what you really mean by "HA". What are you protecting against, what are the costs of an outage of type X and duration Y? How will it affect your organization? What is your role in this organization anyway and what is your time worth? How much time can you spend on this? After that, you have to decide if this requirements allow ...


6

This: Fault Tolerant Shared PERC 8 Card Configuration — [...] The default cache policy for virtual disks created in this configuration is write-through. In this mode, write completion information is returned to the host after the data is written to the disk. is the ultimate performance killer. Change the cache policy to write-back if it is ...


6

You have many options. Which ones you can use depend on how your website is coded. Tightly Coupled, Single State This web-site can only run one instance because of... reasons. Running two in parallel would be an extremely bad idea for some reason. It's pretty uncommon to be this kind of site. CAP Theorem: Consistency over the whole system is paramount, not ...


6

We used to have a problem like this where I'm at. I don't remember the exact details, but the final solution had to do with a conflicting mac address assigned dynamically to a virtual network adapter. Pinning those down to they weren't dynamic helped a lot. You normally don't want to do that because it can make it harder to move a virtual machine to a ...


5

I'd actually recommend Gluster. It is OpenSource, well documented and RedHat recently purchased it. It has a relatively good performance, and since it is a RedHat project now, it is well supported on CentOS. There also is a project called HekaFS, which has the goal of extending glusters Authentication and Security capabilites by adding SSL and other goodies. ...


5

Don't forget to take a reality pill along the way, though. You need to understand the required uptime for your application, and more importantly, the maximum amount of time your application can be unavailable when it does fail. And it will. This second point is critical; I've seen a "five nines" application being managed by a large systems integrator ...


4

Does this necessitate building a virtual failover cluster on top of the physical one, or is this not necessary? It does yes.


4

Do a dig and it becomes pretty clear: $ dig 1channel.ch ; <<>> DiG 9.7.6-P1 <<>> 1channel.ch ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24955 ;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;1channel.ch. IN A ;; ANSWER ...


4

The book is correct, however there are pieces it left out. MAC addresses are not as fixed as you would think, most higher end NICs have the ability to change the MAC address to something specific. Either in the NIC's BIOS or in the driver itself. There are specific ranges of MAC address set aside for 'virtual' systems (see What range of MAC addresses can ...


4

I have experienced the exact same performance issue with a VRTX with the Dual SPERC8. What I have done to work around this at the moment is, change the dual config to a single config. This way I am able to use write-back, which performs way way better. The exact steps: Remove the second SPERC 8 controller Remove the second expander Re-cable the internal ...


4

This is only available in Windows 2012. You'd need to upgrade.


4

Firstly what do you mean by "properly through DHCP"? it's generally a bad idea to use DHCP for servers Secondly it's a really bad idea to use DHCP for cluster VIPs.


4

There is no way that I am aware of using free software to have a pair of two active NFS servers exporting an entire single clustered filesystem. If you are trying to achieve redundancy, you could set up a clustered filesystem and an active/passive pair of NFS servers following Red Hat's Configuration Example - NFS Over GFS (also see cluster administration). ...


4

The MD3200 connects to servers via SAS; so I'm thinking you mean the MD3200i. It's "normal" to separate vLANs for management, iSCSI, and client traffic. You don't mention what kind of cluster software you're running, but for most it's pretty common for it's cluster/heartbeat traffic to have it's own vLAN. Depending on your server and hardware each of these ...


3

I'm gonna make this an official answer. This is a terrible idea. Don't even attempt to do it. I don't care that some guy thought that it might be a great idea what with all the new fangled cloud technology out there. What happens when you lose your internet connection? What happens when your internet connection bounces? What happens when your building ...


3

I use the Microsoft iSCSI target for this - http://www.microsoft.com/download/en/details.aspx?id=19867 My setup is that I have a domain controller in my "lab" network - this is where the iscsi target is installed. From memory, you need to create a VHD, which you can then expose through iSCSI. I then configure the cluster nodes to point to this. I use ...


3

This is not possible without using a shared-storage technology like iscsi. Hyper-V does not support shared SCSI, which is what would be needed to have multiple Hyper-V instances to access the same .VHD file.


3

You can do it in place. You'll have to reboot one or more times, so there will be unavailability, but otherwise you can take a running Hyper-V server, add the Cluster Service, Create the AD Cluster and join the Servers without destroying the current configuration. Side Note: VMs in the Cluster are not automatically highly available. You must explicitly ...


3

I am aware that this is an old question, but I encountered the same issue and wasted so much time getting it resolved that I thought I would share the solution that worked for me. I found the solution to my problem here: http://invendows.wordpress.com/2008/03/06/network-issue-with-hyper-v/ The solution in my situation was to disable TCP Offloading on the ...


3

Use the script on this page to query VM mac addresses: http://www.virtuallyghetto.com/2011/05/how-to-query-for-macs-on-internal.html Match it to your misbehaving MAC address and examine the machine carefully.


3

I have run into something similar in a much simpler Hyper-V environment, and ran across this article at Microsoft. Seems to fit with your situation if the web servers are heavily used. http://support.microsoft.com/kb/974909 - The network connection of a running Hyper-V virtual machine is lost under heavy outgoing network traffic on a Windows Server 2008 ...


3

Someone has terribly misinformed you. MS clustering is only failover : that means that if A is active, it owns the cluster resources : storage, IP, and database services. B just sits there, twiddling its thumbs, until A dies. Then, B will take over the resources.


3

This site is about fact not opinions but I do exactly what you want to do all the time, not in production, I use tin for that, but for test/dev environments it works absolutely great. There's a number of different ways of doing it, we use FC-based RDMs but there are other ways - either way it work, can be a tricky to setup first time, but stays working and ...


3

For your current session? select host_name from gv$instance where instance_number=userenv('instance'); For all sessions: select i.host_name, s.username from gv$session s join gv$instance i on (i.inst_id=s.inst_id) where username is not null;



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