I have a question from my assignment that I 'm looking for answers.
I have a HDD that has Linux on it.  Currently disk has

/dev/sda1 /home /6000M
/devsda2 /var /4000M
/dev/sd3 / +1000M
/dev/sda5 swap +64M

and also 8GB of free space avaliable for later use.  My question is
-I have to add another 100 users.
-Also there have been reports of running out of memory.
-All ram is in use and swap partition is full.
-I have access to a 10.2 HDD to use if I need some extra space.
-This HDD is blank.
-The /mnt directory has no data in it.
-I'm not allowed to keep the temporary drive,so I have to return it.

How can I reorganize my HDD for this situation.  I need at least 8-9 different solution for it.

Your best thing is to add memory. It's not very expensive and will dramatically speed up a memory intensive system.

You should buy another hard drive and put the swap space on a separate drive. Preferably a drive on a separate SCSI channel. If the swap and ram are full you will definitely need to get more of both.

You don't mention how the disk space is currently used (for example: df -h).

How much memory do you have?
What's your budget?
How many users do you have right now?
What is the main focus of the people using the system (programmers or just email)?

Thanks for the answers;
"Your best thing is to add memory ":
According to scenario I'm not allowed to buy ram neither a new HDD.

"You should buy another hard drive ":
My boss is giving me a blank HDD but I have to return it .

"How many users do you have right now?"
Right now I have 400 users and I have to add another 100 users

"What is the main focus of the people using the system (programmers or just email)? ":
Just e-mail

What are the options(at least 7-8 different options) that I can rearrange my HDD for this scenario.

Are you running out of hard drive space or memory?

What is your current disk usage?
What is your processor and what is the load?

If you are truly having memory problems then you need to find the programs that handle email in the smallest possible memory space. What programs are being used currently for mail?

If you are disk space issues then you need to determine what partition is the fullest and how can you allocate it more effectively.

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