Multiple services (fog, censornet, moodle) on one Ubuntu box? Dual NIC?

[ben604]

We're trying to consolidate our many linux servers into one new box with plenty of storage and grunt.

At the moment, we have servers (workstations) for the following:

Moodle
Censornet
Mahara
Zimbra
Fog
Nagios
Xibo

Some of these run on the same box, but none of the critical ones do - Fog, Censornet and Moodle.

Would they all run happily on a new quad-core server? Would we hit a network bottleneck if we were imaging a room while other users were trying to access Moodle? Could we assign a specific NIC for just moodle while the other services use the other NIC? Are dual NICs even supported?

Your guidance would be most welcome!

Ben & ReggieP

[pcstru]

Would they all run happily on a new quad-core server?

That rather depends on the demand (mostly number of concurrent users). It might be OK in a small school BUT imaging from fog may well show up a bottleneck on the network (but depends on the actual config).

I'd be inclined to run them on separate (virtualised) servers and at least split end user/admin/infrastructure. If you don't, you are building up single point of failure around the core services (apache/mysql). But for really useful advice I think we would need a lot more info about the expected loads.

[morganw]

FOG in particular doesn't play nicely with other software as the installer / updater assumes that it's the only thing on the server. . I would look at virtualisation or running in containers like OpenVZ or Linux vServer. Moodle requirements are generally dictated by concurrent users. I imagine Censornet may not perform well as a VM and you may have issues trying to virtualise it as it shipped as an appliance rather than a software package (been a while since I've looked at it though). For FOG have a virtual server for the web interface and TFTP and then deploy images from physical storage nodes, these can be any old PC or server and can be considered disposable. At least if you do virtualise or containerise something you've got the option to move to different hardware with a minimum of fuss if you do get performance issues.

[dhicks]

We're trying to consolidate our many linux servers into one new box with plenty of storage and grunt.

By all means move everything on to one physical server, but as already pointed out you'd do best to split functionality up into separate virtual machines. I generally do this by having a separate boot volume (maybe USB-based flash storage, especially if you get a nice new server with an internal port for just that) and having a larger disk array for virtual machine storage. Linux software RAID (md RAID) works very well, although if you really need disk performance you can use a hardware RAID card (expect to pay at least £300 for a proper hardware RAID card). You can then flexibly split that array up with LVM, assigning each virtual machine an LVM partition.

Linux will handle multiple network cards with no problem - we have one server here with 6 network ports. You can aggregate ports together in the main host and pass the aggregated link to a virtual machine as one connection, or you can pass hardware network ports directly through to virtual machines. Your server needs to have hardware support for hardware virtualisation for this, mind - check before you buy, several processors seem to support standard process virtualisation but not hardware virtualisation.

[localzuk]

I'd not be wanting to put all of those packages on a single server - each one has its own requirements, and even if they are happy to work together now, one of them or all of them might decide in the future to change requirements - eg. one may switch to a new version of a library, but another doesn't, and suddenly one of your services stops working.

Instead, like others have suggested, I would virtualise them all.

I would also not be keen on many of those services sharing NICs - I'd want them all to have their own NIC really, to ensure one service doesn't slow down another (you don't want FOG hogging bandwidth when kids need access to their Moodle accounts for example).

[gshaw]

I'd watch the disk performance as well, a well used Moodle site can hit disks heavily as could web filtering if you've got a reporting system in with it.

Maybe virtualize Fog, Nagios and Xibo but I'd leave your VLE on a dedicated server.

Also if you're going virtual will you have a second server for redundancy? Lots of eggs in one basket otherwise...