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26

Virtual memory isn't even necessarily memory. For example, if a process memory-maps a large file, the file is actually stored on disk, but it still takes up "address space" in the process. Address space (ie. virtual memory in the process list) doesn't cost anything; it's not real. What's real is the RSS (RES) column, which is resident memory. That's how ...


23

Broadly speaking if the virtualisation platform you currently run fully supports the guest OS you're intending to run, virtualisation is a good move. There are some use-cases that warrant more careful inspection: Terminal Services (or services with very high user-concurrency) Funky flavours of Linux Database or Email servers Servers with unusual peripheral ...


14

You could set your network card to have 253 static IP addresses - but that's really not a good way to do this. If you just want to host multiple sites on one IP address, use name-based virtual host instead of IP virtual hosts (the apache equivalent of Host Headers in Windows/IIS). More info... http://httpd.apache.org/docs/2.0/vhosts/name-based.html


11

Linode are who I am with. They have very good pricing, good performance (google search "slicehost vs linode" for example) and a very active support community in the forums and IRC if you need help. Highly recommended!


9

Hyper-V internally allocates memory in 2MB chunks. The hypervisor itself will use 2MB page table entries for efficiency, if possible, if your processor supports Second-Level Address Translation (SLAT.) This will be possible for pretty much any VM with Dynamic Memory turned off. Other than that, no it doesn't matter.


8

From the top(1) man page: o: VIRT -- Virtual Image (kb) The total amount of virtual memory used by the task. It includes all code, data and shared libraries plus pages that have been swapped out. VIRT = SWAP + RES. Where RES means RESident memory (physical memory used). Actually that's not correct (anymore). When it ...


7

The physical memory in the server is a multiple of a power of two, so it will slice evenly if you use other multiples. There may be some incredibly minor improvements with SLAT and such if they're properly aligned too. Otherwise no.


6

Just to clarify what the other answers have said; the limit that's being defined here is basically for your virtual machine's software, not the guest. That is, when your guest OS requests a page of memory, its doing so in defined increments (i.e., 4KB). So if you defined the virtual machine to have 4097KB of RAM, and your host VM was using a 4KB page size, ...


6

I agree with voretaq7 - there is no reason NOT to put vCenter on a AD-joined server when you have the option. A word of advice though - vCenter behaves bad if you mess around with service accounts etc. I'd strongly consider reinstalling vCenter (and all it's children) if you're planning to join the server to AD and already have vCenter installed.


6

Performance would be my main concern; even if you're going to give the VM "direct" access to the physical disks, there's still VM-related overhead, and if you've got any decent load you'll have problems earlier in a VM than you would on a physical machine. But benchmark it, it might work OK for your workload. (For the record, I'd definitely lean towards ...


5

The EULA for OSX precludes it's use on any non Apple platform. You cannot legally do this.


5

The core of the issue lies around the way each domain controller is uniquely identified by the domain, and how domain information is replicated through the system. It's vital that: A) Each domain controller retain its own unique ID, unchanged, at all times. Operations that clone a DC or alter its SID will break this. B) New DCs are only added to the ...


5

"lspci", the unix command, would be the easiest method. It lists the hardware the machine is running on, and if you see things like "Vmware", then the machine is likely not dedicated. However, if the hardware looks like the hardware you are supposed to have, then it's most likely a dedicated machine.


5

If you are using VMWare you can use VMWare converter to conver the PC to a virtual machine. If you are using Microsoft Virtual Server you can use the Virtual Server Migration Kit.


5

You need a ServerName directive in the <VirtualHost> block, so that Apache knows when to serve content from that virtual host.


5

This is fine, but like any other environment, best practices are to have more than one Domain Controller for any given domain. Since you're virtualizing, you'll want each DC to run on more than one piece of hardware. In VMWare you can make DRS rules so that the two DCs don't get vMotioned to the same physical box, I'm sure there a similar thing for Hyper-V. ...


5

This isn't going to work. No modern hardware or hypervisors support NT4. This is a driver/HAL issue and there is no easy way around it. This is why people in your position hoard old junk hardware like the precious.


5

We currently run NT4 on VMware vSphere 5.1 - although Build 799733 no longer supports NT4. However, this is not recommended. Do yourself, and your uncle a favor - update the hardware. Contact the software vendor and get an updated version of their software as well. From personal experience, it's not worth the headache you're about to endure.


4

The reason you're having trouble with this question is you have not sufficiently thought about your desired intention of what each account is going to facilitate. The question you need to ask yourself is; Do all virtual users in this system have mutual access to all managed objects? By this I mean, does virtual user A have the same access requirements ...


4

It looks to me that you are not specifying a 443 port or a 80 port for the virtual host. So everything is heading towards the virtual host which is configured for SSL. So http traffic is not being accepted as it is configured to only accept SSL. Try this NameVirtualHost *:80 <VirtualHost *:80> ServerName blah DocumentRoot /var/www/html/ ...


4

Well, the VMs have to run on something, right? More seriously though, quite often server loads are greater than what a VM can handle, and you need one or more systems to handle it. VMs are great when you have many, lightly loaded applications. When you have something that needs a little more grunt, it makes sense to actually have a server doing the job. ...


4

I'd imagine the rewriting solution gets better SEO-foo (nice term :-P) since it's usually considered best to have one canonical domain that everybody gets sent to for a particular set of content. In other words, having two different domains that produce the same results from the server can split your site rankings between the two domains, reducing the value ...


4

You can turn off the VM, then select File -> Export OVF Template, then export the template and deploy it somewhere else. To do this with minimal downtime is pretty hard using plain ESXi without the paid-for vSphere.


4

Virtual Media tends to work decently on the LO100i devices like the one in your system. Are you licensed properly under the Application License Key Menu? Otherwise, when you press "Connect", you should see the file path of your .ISO image change to a URL containing the IP of your client computer and connection type (e.g. /192.168.10.55, 0, USB 2.0). If it ...


4

CARP will handle moving the IP from box A to box B (and optionally back again), however it won't do anything else -- If you're absolutely sure you don't need to do anything else (like change a DB from slave to master, Start or Stop some service, etc.) CARP should be adequate for your needs.


3

The above answer by ewwhite is almost perfect. What is missing here is that the virtual media feature does need a 5901 TCP/UDP connection between the server and the client, as ewwhite says, but this must be in both direction, so if your client is behind a router you need to set up a forward rule in the router for packet at port 5901 *from the server* (the ...


3

If you can get your hands on an actual IOS load, you should check out the GNS3 Network simulator. With it you can build virtual routers running real versions of Cisco IOS and test out almost anything you need. It's not all that easy to setup, but the documentation is very good and if you read it, you can do it.


3

Such a topic has to be considered in the context of your environment and cannot be definitively answered for you as a general concept. You need to consider everything, starting with whether or not a virtualised machine can provide the performance you require. This includes such things as the storage system being able to keep up. That of course tends to be ...


3

We run our servers in both virtualized environments as well as in their native environment. This goes for both our Linux based servers as well as our Windows Servers and Desktop. Saying one is better than the other is going to completely depend on what you need to do. Sometimes Virtualization is better, sometimes not. Virtualization Pros: Ease of ...


3

Any request with a Host header that does not match the ServerName in any <VirtualHost> section falls through to the "main" server configuration. As such here is no way to outright prevent a connection, but you can "short circuit" the request by sending back a blank response, or by pointing DocumentRoot somewhere that doesn't exist.



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