which is lightest linux distro to install utility softwares in vm environment? - linux

My application is running on ubuntu 14.04 vms. And it is decided that we install utility software like security Gateway , imq on individual vms.
I think it is overkill to run a security gateway on full fledged OS. Is there any better way, wherein i can use a OS with lightest memory, filesystem and cpu footprint ?
Just as some applications can get their work done using lighttpd in-place of a complete webServer.

I am need of a lightweight server image, which will be easier to store as well . Lubuntu takes 800+ MB.
I think https://help.ubuntu.com/community/Installation/MinimalCD will do.
Let me try that and post the results.

Related

Is running a Linux container on windows AWS instance possible?

I'm trying to run a Linux (ubuntu LTS) container inside a windows server 2019 OS. The problem is that the windows OS runs as an AWS instance.
There have been problem for me trying to achieve this and I've been reading somewhat different opinions on the internet regarding whether or not it is possible. Some say it will be possible on a .metal instance which is bare metal. Currently I've been trying running it on a regular t3 instance with has virtualization type HVM.
To sum up my questions are:
Is running a linux container on windows aws instance possible?
If yes, how?
If not, will it be possible on a bare metal instance?
Please keep in mind that I need the container to run in a Windows environment due to multiple tasks the the OS needs to achieve (and I don't want multiple instances)
In order to use Docker Desktop on Windows, you need either Hyper-V or Windows Susbsystem for Linux enabled (which at its turn requires Hyper-V). Both solutions demand of VT-x capabilities, but you're running inside a VM, which means that is not so easy to achieve.
It is called "nested virtualization", and it is not supported in common EC2 virtual machines. (source)
You can certainly run Linux containers on a bare metal Windows instance (but why you should? it is way cheaper and simpler to create a Linux virtual machine on EC2 and communicate it with your Windows host). Should still that be your purpose, you can install Windows Server 2019 with Hyper-V. (tutorial)
Another alternative for SMALL, SMALL things, that could work without nested virtualization (I haven't tried), would be using WSL1. (more info)
WSL1 uses a compatibility layer between Windows and Linux system calls, without actually virtualizing the operating system. Some folks have been able to install Docker 17.09 on WSL1, but this is a very adventurous path I would not recommend taking.

Cygwin vs Linux Virtual Machine for Development?

< skippable part >
I work in IT (mostly desktop support and network administration) in a Windows environment, and I occasionally program.
A couple weeks ago, I decided I couldn't be as effective as I want to be without a Bash environment for my command prompt needs. This is especially true when I am using Ruby and git. I used Msysgit for a while, but I just didn't like how it wasn't extensible like Linux. So, I installed Cygwin and played around with that for a couple weeks.
As great as Cygwin is, it seems like it is meant to be a suped up command prompt, and its compatibility with Linux is just a pleasant side effect. This especially became evident when I tried to upgrade Ruby to 1.9.3 (it worked, but it wasn't straightforward), install rvm (never worked), and install RMagick (may or may not work, but looks like a headache).
So, now I'm considering running Linux in a virtual machine. But I'm worried that might be another can of worms and I'll have wasted hours before I find that out. I like that Cygwin runs in Windows and I get to use my IDE, user folder, and more with it. But I don't like that support for it is not as thorough as for a major distro.
< /skippable part >
Does anyone here have insight on using Cygwin vs running a Linux virtual machine?
Any advice on setting up a Linux development environment in a virtual machine within Windows?
I have faced common issues before, and the best solution according to my experience is just 2 workstations :).
Apart from that having Linux running in a virtual environment is way better.
First of all, you will have full Linux capabilities (except 3d acceleration, but you probably don't need that).
You will have the capability of creating snapshots and revert back to them when things go wrong!
You can start multiple environment using templates, which is very convenient.
The only downfall I can think of is performance issues of the host machine.
If it's a normal workstation/PC, an IDE + one virtual machine + a 100+tabs browser just makes it slow.
1: cygwin is good for quick hacks, and for being able to acces host-os resources(you can run IE for example in a bash script). For something tightly integrated and some "real" word, go to a vm. It will emulate everything and separate development from the real machine, and this may be a good thing in some cases... as a plus it simulates a real server:)
2: in virtualbox at least, you have shared folders, and you can share a local folder, and see it in the vm as a local folder(local or as a windows share..it actually depends). Then you can use that "entry point" to symlink stuff into the vm, and do the things you need with the real files being located in the real(host) machine
SSH into a linux box. This is what everyone does. Why isn't this the answer?
There is something I have heard of called Cooperative Linux. It runs Linux alongside with Windows kernel so you can use them at the same time. I've never used it, but here:
http://www.colinux.org/
What I think now is getting the pros of 2 options is using
Docker
, it is giving you cygwin simplicity and VM functionality with better performance.
Linux in a virtual machine will give you the experience you want more than cygwin or any mock shell as I like to call them.
Running VM's though require a lot of ram depending on whether you want a desktop version of linux or just a command line version.
Myself in work I have a pc with 8gb of ram and I run ubuntu 64bit as main OS, two ubuntu servers (these are for dev environments two different projects) and a windows 7 VM and a win XP VM.
I can run the two ubuntu servers and one other VM at the same time, key here is more ram if you want to be able to do VM's.
If you're going to be working with Ruby then get an Ubuntu virtual machine up and running :) I've not tried Ruby, etc on Windows but I have heard that it is a pain to setup and configure. I use a Mac for all my Rails development so I cannot comment on the Windows side for that.
As for virtual machine creation, I prefer VMware Workstation, however there are free alternatives such as Virtualbox and VMware Server.
I'm using a Linux VM within a Windows seven environment as this VM is as representative as possible of the final production environment. The whole setup is binded to the Eclipse IDE under ms-Windows seven. So this is really great for local full testing, before committing or tagging the tested version to the production servers.
As you mentioned as well, this takes some time to get properly setup and fully configured. So if your need is only for little tricks or tasks, you may keep using cygwin. For example, I faced significant issues to configure perl and compile mysql within cygwin. So it's ok for basic usages, but not to fully take advantage of a full linux environment.
Your choice strongly depends on the final server setup purpose. A VM will do it whatever your need is. The setup cost for it is higher, so this time investment must be used often to get returned.

building linux kernels

i Just got the book Linux Kernel Development by Robert Love . It has lots of places where you are required to modify and build the kernel . So how should i go with it . Is it better to use a VM , or should i somehow get a proper test machine for it , since i dont want to goof up on my system and data.
A VM has the advantage of offering snapshots. These allow you to save the state of the machine - if the kernel build doesn't work you simply restore the snapshot, and you are able to take as many snapshots as you have disk space to store them. You are also able to clone and re-deploy the VM image, so you have many identical systems to test on.
The same experiment on a physical machine would require far greater effort (ghosting/cloning the disk, re-installing the OS etc).
VirtualBox is free, cross-platform virtualisation software.
There are a lot of tutorials on the web about this topic, e.g. here:
http://www.digitalhermit.com/linux/Kernel-Build-HOWTO.html
http://www.kernel.org/pub/linux/kernel/people/gregkh/lkn/lkn_pdf/ch04.pdf
You could do either or both. An alternative somewhere in between is to setup a dual boot. This is a little riskier than a VM, but not too much.
coLinux
or run linux iso image using QEMU on windows

Running VMware in VMware?

We have a physical machine that runs VMware and hosts a VM we use for SharePoint deployment testing. That machine is old and dying, and my employer's network czars are heavily pushing hosted VMs as a replacement for outdated physical servers. I was curious about whether it's possible to run VMware inside VMware, and if so, whether there are severe performance implications. We don't require extreme performance from this setup, since it's just used for SharePoint testing and the associated SQL Server is on a different box. My guess is that we can't just use the primary hosted VM for our testing because we'll want to roll back occasionally and otherwise have more control over it, and getting buy-in for that from the network folks is unlikely. Does anyone have any experience with this?
edit: I know this nesting certainly isn't the preferred option, but (1) we want the flexibility of being able to use VMware snapshots at will and (2) the network folks will not allow us to arbitrarily roll back to a previous point in time because of the potential for removing mandated security updates. My guess is that a local desktop machine running VMware Workstation might just be the way to go. The hosted option seems attractive if it will work though since it's less machine maintenance for me to deal with.
The technical limitation with running VMware inside VMware is that VMware, Virtual PC, etc takes advantage of the Virtualization features present in modern CPUs.
If you have two or more hypervisors are both trying to control Ring 0 then there will be problems, this is something that I've encountered while trying to run both VMware and Virtual PC simultaneously on my desktop - one will error out/crash.
If your hypervisor can interact with the 'parent' hypervisor, then you'll be OK. Alternatively if the child hypervisor doesn't try to use the CPU virtualization features, or entirely emulates the CPU (such as QEMU) then you should also be OK.
Basically old-style hypervisors on old CPUs use Full virtualization (slow) which would be capable of nesting with a heavy, heavy performance hit. modern Hypervisors/CPUs use hardware assisted virtualization (near native performance) and you'd be hard pressed to find a hypervisor that is designed or capable of nested virtual machines.
Finally, I'd really advise against running dev/test VMs on the same physical server that is running production VMs. There's just too much to go wrong and security implications - you need to manage the dev/test environment and it sounds like you shouldn't have access to production environment. Likewise you probably don't want the operations team messing about with your test environment.
UPDATE: ESXi 4 now supports virtualizing itself. See this article for more information
I've never run VMware in VMware, but I've run VirtualPC inside VirtualBox without problems, so there's no fundamental reason it shouldn't work I suppose...
It sounds to me more like you have a problem with the inflexibility of your "network czars" than any technical one. If you're a developer or QA you need a testing environment where you can fool around with outdated (and potentially insecure) versions of the OS and applications, without putting the rest of the company network at risk.
Ex-VMware employee here.
Firstly, when you say Nested VMware I will assume you mean Nested ESXi. (You could also mean Workstation, Fusion, or Player).
Nested ESXi environments are unsupported and should not be used for production. These scenarios are not tested in QA and not guaranteed to work. In short, if you experience any kind of problem, VMware will not help you with this Nested ESXi setup.
With that said, yes you can do it and yes it does work. A lot of people use nested ESXi in their labs but not in production. Previously there were special configuration file edits that were necessary for nested ESXi to work. I have seen environments with even 3 layer nested ESXi servers (ESXi vm on and ESXi vm on a physical ESXi host). More recently there is the ESXi appliance which makes this much easier.
Have a look here:
http://www.virtuallyghetto.com/2015/12/deploying-nested-esxi-is-even-easier-now-with-the-esxi-virtual-appliance.html
I ran into this same problem. I work at a large company where our entire infrastructure is virtual, so if you need a server you get a VMware VM. So I had a couple of Windows 2003 Server Standard Edition based Guest VM's that had 6GB of memory and 200 GB of disk space, but I wanted to run linux and a LAMP stack on them. So I tried to install VMware Workstation on one and I got an error message saying it couldn't be installed within a VM. I also tried Microsoft Virtual PC and got a similar error message. I installed Sun's VirtualBox and that installed fine, but I couldn't get the networking to work w/in the guest Ubuntu OS. My next step is to try QEMU although performance might become an issue.
You ought to have a look at Mainframes - they are Virtualised from the word go:
Hardware - runs Hypervisor Type 1 - Level 1
on this you have zVM - Type 2 Hypervisor - Level 2
on this you have zOS - your main big operating system - Level 3
and/or
on this you have zLinux - Level 3
and/or
on this you have zVM for testing next version - Level 3
and/
on this you have zOS for testing zVM plus zOS both at next version - Level 4
So going down to level 4 is pretty common
Mind you on a Mainframe you can have 1000's of VMs running at the same time - and most sites who start using zVM/CMS and zVM/Linux usually do.
I can see two solutions for this (three if you count a VM inside a VM which is just crazy).
New hardware, which should be robust enough to handle several VM's used specifically for testing (sharpoint, etc.). In this situation your team could be given more rights without affecting non-testing VM's.
Sharepoint test VM's are moved to the main VM pool and those who need access are given the ability to checkout/deploy/rollback testing resources. This could be direct through VMWare tools or through an internal project that works through a VMWare API.
This should be a joint decision between Network/Dev/Testing.
JFYI:
I tried installing and running VMware ESXi server host(child ESXi server) as a virtual machine(on parent ESXi server) and it runs however you can not run any VMs under child ESXi server.
I am doing practice of VMware vSphere Data center virtualization on single Physical machine. There is VMware Workstation installed on Windows 8 OS. In VM Workstation, I have installed Windows Server 2008 OS, VMware ESXi OS and created the VMware Data center LAB. There is VMs running in LAB, and its confirm that We can user VMware in VMware. But it depends on your need, and Products which is chosen.
You can install ESXi on VMware Workstation, it's usefull to learn ESXi, so there in no reason run VMware in VMware.
Yes. You can run VMWare inside VMWare. Though its not officially supported, You can deploy VMs in the child ESX. I have checked for an advanced feature like PassThrough the HBA card but which was not available in child ESX, hence I could not provide a LUN from array.
So in production its better to not use this.
But for training and practices this can be used.
You can do that.
You can install vmware esxi inside virtual machine of another vmware esxi.
But the performance will be very bad.
Totally works.. totally can't do it other then for some kinda testing or some kind of educational purpose, because you won't get support. and from my limited experience it doesn't perform that well.
Yes, you can, VMware can even detect if it's running inside of another vmware machine and warn you that VMception will cause worse performance. which it will, trust me, just try to get the version the virtual machines work best in a physical machine, as to get as much performance possible.
"whether it's possible to run VMware inside VMware" What?
I can run Windows with Sharepoint in a VMWare machine that's hosted somewhere.
Or, I can run Windows with Sharepoint in a WMWare machine that's actually a VMWare machine that's hosted somewhere.
Why on earth would I add a level of nesting? Why not just go with Windows with Sharepoint hosted somewhere?
You can have any number of VMWares running on a single host. Lots of different versions doing lots of different things.
Nesting them doesn't make sense.

Is Ubuntu JeOS good for production purpose?

Actually I will want to use that JeOS for our webserver. Is it a good choice?
Thanks for piquing my interest. From the Ubuntu website:
Ubuntu Server Edition JeOS (pronounced
"Juice") is an efficient variant of
our server operating system,
configured specifically for virtual
appliances. Currently available as a
CD-Rom ISO for download, JeOS is a
specialised installation of Ubuntu
Server Edition with a tuned kernel
that only contains the base elements
needed to run within a virtualized
environment.
It looks promising to me - I run several full Ubuntu 8.04 VMs so I'll certainly check it out. Why not just try it?
Be aware that the kernel it installs is striped down to only have the stuff required for virtual machines, therefore you might have problems accessing the network from a real machine. (Note that the install-CD kernel isn't the same as the installed kernel as well).
If you can bypass that (IIRC I booted from the CD, and downloaded the normal server kernel and it all worked fine), then you end up with an absolutely minimal Linux system, but backed by the full Ubuntu repositories, so it's an excellent base for a server.
Also note minimal really means minimal - no cron by default for example.
Is it a good choice?
If you plan to run JeOS in a virtual machine, then yes, this is a good choice.

Resources