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Setting up a Minimal Samba Server in Fedora Core 12

elran — Fri, 18 Dec 2009 04:58:47 +0000

Goal:
Minimal FC12 Samba install with low RAM usage, high security, and least amount of configuration.

Why?
Quickly turn an older machine into a modern Fedora Core 12 file server compatible with linux and windows clients. Less software installed means less setup, less maintenance, less updates, and less chance of human error somewhere along the way. The theory here is, the system starts out relatively secure and (if kept up-to-date) should remains so over time.

Side Note:
There are definitely many other ways to go about setting up a Samba server, much of which depends on your networking environment and overall requirements / constraints. This article is meant more as a guide – my notes which describe the method i happen to use – so that if i have to, i can do it all again.

Assumptions:
- Comfortable with install and use of Fedora Core Linux OS (command line)
- Basic understanding of networking concepts (setting up a static IP)
- Some experience with editing the smb.conf file

Features:
- No GUI / Desktop Environment
- Low RAM usage: boots up @ ~80MB with smbd and nmbd running
- SELinux and iptables firewall enabled / configured for use with Samba
- Samba Security level = User

System Resources:
CPU: AMD @ 700MHz
RAM: 192MB

Steps Involved:

Download and burn the Fedora-12-i386-DVD.iso file to dvd
Boot from the disc and go through install process (with less that 200MB RAM it defaults to text mode install – you can also force a text mode install at the boot: prompt by typing: linux text)
Once install is completed and system is rebooted, login as root
Check that networking is up
- type:
```
ifconfig
```
(see if you have an IP address)
- type:
```
dhclient eth0
```
(to use dhcp for now)
Bring the system up to date
- type:
```
yum check-update
```
(to check for updates first)
- type:
```
yum update
```
(say “yes” to install the updates)

- type:

yum list installed

(to see a list of all installed packages)

Check to see what package “groups” got installed by default
- type:
```
yum grouplist > grouplist.txt
```
- type:
```
cat grouplist.txt | more
```
Remove any unwanted package groups
- type:
```
yum groupremove "Mail Server"
```
Add the Samba package group
- type:
```
yum groupinstall "Windows File Server"
```
Configure Samba by editing /etc/samba/smb.conf
- Note, for Vista support (in the Global section) add:
```
client NTLMv2 auth = yes
```
- Note, to hide unreadable files like /lost+found/ (in the Global section) add:
```
hide unreadable = yes
```
- type:
```
testparm
```
(confirm output has no errors in it)
Deal with SELinux security policies (see default smb.conf file for details)
- type:
```
setsebool -P samba_domain_controller on
```
- type:
```
setsebool -P samba_enable_home_dirs on
```
- type:
```
chcon -t samba_share_t /path-to-mounted-directories
```
(remember to mount any/all directories first)
- type:
```
ls -ldZ /path-to-mounted-directories
```
(to confirm it worked)
- Note, for existing shares, to make sure this affects all files and folders recursively add:
```
chcon -R -t samba_share_t /path-to-existing-mounted-directories
```
- Note: to completely disable SELinux protection for smbd daemon (not recommended) type:
```
setsebool -P smbd_disable_trans 1
```
- Note: you can temporarily disable SELinux by putting it into permissive mode – type:
```
getenforce
```
to find out whether SELinux is in permissive [0], enforcing [1], or disabled [2] mode.
- Note: to put SELinux into permissive mode (for testing purposes but not recommended) type:
```
setenforce 0
```
Add samba users
- type:
```
useradd john
```
- type:
```
smbpasswd -a john
```
Configure the firewall to accept samba connections
- type:
```
system-config-firewall-tui
```
(add an asterix next to the line: “Samba”)
Configure the network to use static IP/netmask/gateway/DNS info
- type:
```
system-config-network-tui
```
- select: [Edit a Device Params] and remove the asterix from the line: “Use DHCP”. then, and add static info
Configure the network to use a static Hostname and DNS address (note: DNS settings may not be required)
- type:
```
system-config-network-tui
```
- select: [Edit DNS configuration] then, and add static hostname and dns info
Get the network, smb, and nmb to start automatically next time you reboot
- type:
```
chkconfig --level 3 network on
```
- type:
```
chkconfig --level 3 smb on
```
- type:
```
chkconfig --level 3 nmb on
```
- type:
```
chkconfig --list network
```
(or smb, or nmb to confirm it worked. you can also leave out the servicename to see a list of all services)

Reboot.
Use another computer to check that everything went well.

How to increase the size of a VMware vmdk file formatted as linux lvm

elran — Fri, 25 Sep 2009 05:03:33 +0000

VMware can run many cool operating systems on a single host computer. But, having run the software for an extended amount of time, i eventually always run out of space on my guest OSes. This happened a few times before, but it wasn’t until my VM really froze up on me that i figured it was time to look into extending or expanding the current virtual disk i had in use.

Have you ever tried increasing the size of a vmdk file / virtual hard disk ?
It’s not that easy.. and it’s kind of confusing.

So, once i finally figured out how to do it, i thought it would be useful to write it down so that i wouldn’t forget next time this happened. Here goes..

In my example i have:
- a Windows Vista host OS running a Fedora Core guest OS
- an 8GB vmdk file (formatted as Linux LVM – fedora fs) on the guest OS which i have backed up before attempting anything here !!!

I want to:
- increase the 8GB vmdk file to 16GB
- not lose any data saved on the vmdk file
- not move any data off/on the vmdk file

Follow these Steps:

Download and Install: VMware Workstation for Windows (trial)
Note the location of the VMware Workstation folder (after install) – in my case it’s “C:\Program Files\VMware\VMware Workstation”
Open a Windows Command Prompt and navigate to the folder where your vmdk file resides and execute the following command:
"C:\Program Files\VMware\VMware Workstation\vmware-vdiskmanager.exe" -x 16GB "Name of Your Virtual Disk File.vmdk"
Ok, now you just made the disk twice as big but you can’t use the space yet because it’s inactive, unpartitioned, unformatted, and still utterly useless to us. (but not for long)
Next, boot up the guest OS and log in as root. Verify that there is in fact a large amount of unallocated space/sectors by typing the command: fdisk -l
Then we’ll partition and format the new portion of the disk. First select the disk: fdisk /dev/sda
Type “n” at the fdisk menu to create a new partition
Type “p” for primary partition, and then select the appropriate partition number, as well as first and last cylinders to set how large to make the new partition (defaults – ie: use all the free space – worked well for me here)
Type “t” to change the partition’s system id, then type “8e” to switch it to Linux LVM
Type “w” to write the table to disk and exit fdisk. You might get a warning about needing to reboot for changes to take effect – either way, reboot your guest OS just to be safe.
Once rebooted, log in as root again and verify the new partition exists. Type “fdisk -l” to see a list of partitions. In my case, the new partition is: /dev/sda3
Now comes the confusing part. We’re going to merge the new partition into the current Volume Group (which is just what fedora calls it’s own virtual disks that are made up of a bunch of virtual LVM partitions). So, first, to “create” the necessary “physical volume” from our newly created disk partition (/dev/sda3) first type: pvcreate /dev/sda3
You need to find out the name of the Volume Group before you can extend it to include the newly created physical volume. Type: vgdisplay and look for the first line, “VG Name” – in this case it was VolGroup00 [thanks agm]
Next, you need to extend the Volume Group to include the newly created physical volume. Type: vgextend VolGroup00 /dev/sda3
Then, type: pvscan You should see the new partition (/1dev/sda3) in the list of partitions and the total should read approximately 16GB (the amount we set earlier). In my example, it said 15.75GB
Now type: lvextend -L+8GB /dev/VolGroup00/LogVol00 to increase / extend the Logical Volume by 8GB (to a total of 16GB).
Finally, to resize the filing system type: resize2fs /dev/VolGroup00/LogVol00

Now your fedora guest OS should have twice the amount of space and your VM should be running smoothly.
Repeat this process if / when the vmdk file gets filled up again and runs out of space ;)

VMTN Virtual Appliances – the 52 that looked interesting to me

elran — Tue, 16 Jan 2007 19:31:44 +0000

I have been using vmware for a while now..
Recently, i got sucked into the VMware Technology Network (VMTN) site – again – and browsing through the many virtual appliances available for download, i managed to compile a list of 52 of my favorites.
All you need to do is download the free VMware Player, which will let you run one of these virtual appliances on any Windows or Linux desktop.
Great for testing, coding, and learning. You can read more about virtualization on the VMware site.

The List of 52 Appliances (in no particular order)

Sound editing on a budget with Linux

elran — Fri, 14 Oct 2005 15:37:43 +0000

About a year and a half ago, I did some initial research to try and find a decent sound editing solution for a Linux machine i had recently built. The computer was running RedHat Fedora Core 1, which was still pretty new at the time, and it had almost everything you’d come to expect from a modern desktop OS. Softwares like Firefox, Evolution, Open Office, and Gimp made it easier to start comparing Linux as a desktop alternative to Windows or OSX. With this in mind, i was beginning to think that it might be the right time to consider recommending Linux desktop installations to some of my clients.

However, Linux sound editing is still arguably one of those gray areas where a single, dominant software has yet to emerge. This makes it difficult to compare to popular propriety software solutions. Furthermore, it meant that i was going to have to test out a whole bunch of softwares before i could make an informed decision as to which i might like best.

Well, i must have tried about a dozen audio softwares before coming across Audacity. Many people recommended it and i knew that it was supposed to be very powerful. Although, i must admit, it seemed modest compared to some of the things i had seen in similar audio softwares. Still, Audacity was stable and worked well (which was more than i could say for some of the other apps i tried), and that was all i wanted in the first place.

I still have the bookmark for the original article on OSNews entitled: “Professional Audio Closer to Linux“. It’s a bit dated by today’s standards [2002-08-10], but you can see (by how long the list is) that no single software had emerged as the dominant choice. Ironically, the article starts off by referring to “how much more viable Linux is today as a professional (or semi-professional) audio platform than it used to be two years ago.” I suppose i should try to avoid making a similar statement in this article – truth is, i’m not sure that this statement would be any more accurate today than it was back then.

If you’re interested, here’s 2 more lists of audio softwares that run on Linux; one from LinuxLinks.com and the other from Linux-Sound.org. But if you don’t like long lists or haven’t got the time to try out more than 3 or 4 softwares, then i would recommend reading “Editing audio in Linux” by Ian Smith-Heisters of Arstechnica.com. It actually only profiles 3 Linux based audio softwares but a fourth one, called Hydrogen, is mentioned in the comments of a related post on Digg.com that might also be worth checking out. Ian does an excellent job of detailing the differences between Ardour, Audacity and SND with reference to what he calls “industry-standard apps” like ProTools, Logic, Nuendo, and Digital Performer.

He highlights the features and capabilities of each audio software (complete with screenshots), and explains any Linux related concepts like ALSA and ESD that surround the topic. The general concensus seems to be that all 3 apps are great at what they do. More specifically, Audacity is the easiest to use (probably why i initially stuck with it over a year ago), Ardour has the most features that can be compared to industry-standard apps (good for larger projects), and SND is, well.. mostly for geeks (but also the fastest and most versatile).

What i actually found most interesting about the article was towards the end when Ian talks about how difficult it can be to compare some Linux apps because “they don’t have proprietary analogues”. Meaning, there’s nothing really like them, or they cannot even be compared. He goes so far as to say, “Editing audio in Linux may be becoming a significantly different occupation than editing using proprietary platforms.” Even if you’re not so much into sound editing but are interested in open source versus proprietary systems, you can skip to page 5 and see what he means by this statement.

I think Ian’s statement is similar to the way i feel about the idea of Linux as a complete desktop alternative to Windows or OSX. Sure, it can do everything that other operating systems can do (and then some) – but you’ve got to speak Linux (and to a certain degree think Linux) to get it to do so. With sound editing there are definitely specific concerns related to hardware compatibility, etc. That means right away you need to be both knowledgeable in sound editing and audio hardware to make it work. But if and when you do get it to work, it has the potential to do things you just can’t do with proprietary software.

So, unless you’re willing to put in the time to learn something new, and often as a professional you simply can’t commit a significant amount time, you’re not going to find Linux to be a very satisfying alternative. You could still experiment with Linux on a second computer without disrupting your regular workflow until you felt comfortable enough to make the switch. But for a client who is determined and well informed, Linux is open and free, which makes it particularly attractive to those on a small budget, and which also means it is only going to grow and get better with time.

[ If you enjoyed this article, you might also like: "Windows to Linux: Baby Steps" or something else in the Linux Category. ]

3 different ways to walk away from Windows

elran — Sun, 14 Aug 2005 15:45:52 +0000

As a follow up to an earlier post entitled: Windows to Linux: Baby Steps, and because i just can’t stop investigating new operating systems, i’ve decided to give a brief description of 3 distros that caught my eye this week. While all of these distributions have easy of use (installation, familiarity, etc) as a major priority, each one offers a unique approach and so might appeal to different people depending on their particular needs. That being said, any one of them might serve as an excellent stepping-stone for someone looking to walk away from Windows and all things Microsoft.

The first distro is called SLAX -

From their website:

“SLAX is a small bootable CD containing the Linux operating system. It runs Linux directly from the CD (or USB) without installing. The Live CD described here is based on the Slackware Linux distribution and uses Unification File System (also known as unionfs), allowing read-only filesystem to behave as a writable one, saving all changes to memory.”

What this means is that anyone can run this CD and test out Linux without making any changes to their hard drive, or otherwise affecting their current Windows based machine. Take out the CD and reboot, and everything is back to normal.

The second distro is called XPde –

From their website:

“XPde is a complete desktop environment for Linux on x86. It tries to make easier for Windows XP users to use a Linux box. Nothing more, no clipboard compatibility between Gtk and Qt applications, no emulation of Windows applications, no unification on the widgets of X applications, just a desktop environment.”

XPde is made to look, as much as possible, like Windows XP. The idea was to ease the transition from Windows to Linux by designing an operating system that was visually familiar, with none of the extra things that might overwhelm a new user.

The third distro is called PC-BSD –

From their website:

“PC-BSD has as its goals to be an easy to install and use desktop OS, which is built on the FreeBSD operating system. To accomplish this, it currently has a graphical installation, which will enable even UNIX novices to easily install and get it running. It will also come with KDE pre-built, so that the desktop can be used immediately.”

The BSD family of operating systems is traditionally thought of as more difficult to install and operate than others. PC-BSD hopes to break away from this commonly held misconception and address these issues directly by focusing on simplifying the user’s experience. The result is a minimalist approach, with a clean, user-friendly feel.

I think that if you’re really nervous about installing a different (not Microsoft) operating system, or you’re just moderately curious, then you might go with the SLAX bootable CD. If you’re a Windows XP user, and you’re sick of all those browser vulnerabilities and viruses, you would probably like XPde best. Otherwise, if you’re looking for speed, stability, and all the functionality of a UNIX operating system, try out PC-BSD.

Windows to Linux: Baby Steps.

elran — Thu, 11 Aug 2005 23:11:27 +0000

Every so often, i get myself into an uncomfortable situation that involves me trying to explain to someone why they should to switch from Windows to Linux. It goes something like this, “because it’s faster, more secure, …” — but for some reason i just never know where to begin. I end up either confusing the person or just scaring them off with too much technical jargon.

I thought it would be a good idea to make a list that compared Windows to Linux softwares, side-by-side. That way, i could describe the difference between the two operating systems in terms that people were already familiar with. Try Firefox instead of Internet Explorer, Open Office instead of Microsoft Office, Thunderbird instead of Outlook Express.. and so on.

All of these alternative softwares are free to download (there’s a good reason, right?) and can be installed on a system running Windows. The idea was to prepare the person for an eventual switch to Linux. So if those 3 applications are the only ones you even use, go ahead and give them a try. You too could be running a Linux desktop in the near future.

Unfortunately, these days the vast majority of Windows users demand a lot more out of their desktop systems. When comparing softwares for things like sound, gaming, viewing dvds, and different graphics editors – there may not always be a clear Linux alternative. I was relieved to find out that there is a site called Grokdoc that has taken on the challenge of maintaining such a list, so i guess i won’t have to. Lucky me.

If you were looking for a starting point, i would recommend the page entitled: Switching to Linux, which is a very complete step by step for first timers. It does a good job of bringing together info from many different sources. There is also a page called Application Crossover Chart, that does a side-by- side comparison of softwares with links to many Linux alternatives, but there isn’t as much description, so it is more useful to have just as a reference.

I guess i’ll end off by quoting what someone once told me when i first starting asking about Linux:

“Just read a lot.”

Damn Small Linux, damn.

elran — Wed, 29 Jun 2005 06:26:23 +0000

Because i like to make it my business to know (at least a little) about the top 10 Linux distributions, i had to look into Damn Small Linux. It crept it’s way up in at #10 and we’ll see where it goes from there.

It is a minimalist distro, 50Mb total size, and could even fit on a USB memory key. Anyway the people at Distrowatch.com describe it as: “a nearly complete desktop, including XMMS (MP3, and MPEG), FTP client, links-hacked web browser, spreadsheet, email, spellcheck (US English), a word-processor, three editors (Nedit, nVi, Zile [emacs clone]), Xpdf, Worker (file manager), Naim (AIM, ICQ, IRC), VNCviwer, SSH/SCP server and client, DHCP client, PPP, PPPoE, a web server, calculator, Fluxbox window manager, system monitoring apps, USB support, and soon it will have PCMCIA support as well. If you like Damn Small Linux you can install it on your hard drive. Because all the applications are small and light it makes a very good choice for older hardware”.

Symphony OS Alpha 3

elran — Wed, 29 Jun 2005 04:40:03 +0000

[ page last updated: Aug. 14, 2005. ]

I have to remember to keep an eye out for this up and coming Linux Distribution. From the screenshots [ 1 | 2 | 3 ] on their site, it looks really different. It is still only in the alpha stages at this time, and i should probably wait at least until a beta version comes out before i try to install it / test it out.. but who know’s, maybe i’ll try it out sooner.

It kind of reminded me of what i had hoped the Project Looking Glass would be. Looking Glass is an Open Source Operating System described as an innovative 3D environment and is currently being developed by Sun Microsystems.

The Alpha 4 version is supposed to have some major improvements, it is due to be released sometime in july ‘05. Will definitely check back soon.

Update: Symphony OS Alpha 4 version is now available for download (as of Aug 3, 2005). New features include: graphical package manager (Synaptic), better search capabilities (Beagle), new configuration tools, and more. Looking forward to the Beta 1 version, which is the next build to be released.

final touches – smoothwall

elran — Tue, 28 Jun 2005 03:21:31 +0000

here are 6 things i can still do to modify / improve my smoothie:

1. [2.0] Guardian – Reactive Firewall (v2.1)
2. [2.0] DShield Log Submission & Blocklist v.1.5.2
3. [2.0] MyNetWatchman – Intrusion Escalation (v1.2c)
4. [2.0] A BLUE interface (in progress)
5. [2.0] LaBrea 2.5 Stable 1 – Honeypot / IDS daemon
6. [2.0] Firewall Log Filters (Activity Threshhold and Not-IPBlocked)

here are the mods currently installed:

1. [2.0] ClamAV 0.85.1 – Anti-virus software
2. [2.0] Dansguardian GUI v2.8.0.3 and clamav 6.3.8 + Logs
3. [2.0] Bandwidthd – IP / Subnet accounting by protocol
4. [2.0] updatesnort PACK – one-click Snort rule updating
5. [2.0] Logs mod (v.1.1.2) – browse logs the easy way
6. [2.0] iftop – Find out why your ADSL line is so slow
7. [2.0] DansGuardian 2.8.0.3 & AntiVirus 6.3.8
8. [2.0] IDS Control v.1.0.1

and finally, here’s a list of all smoothwall mods from the smoothwall forums site:
» View topic – Summary of Mods – community.smoothwall.org

smoothwall, kiwi, and syslog

elran — Tue, 28 Jun 2005 03:02:17 +0000

this is a how-to on setting up smoothwall, kiwi, and syslog – link leads to the smoothwall forums.

also check out this freeware Syslog Daemon for Windows – the site has other related resources.

ex:
. Kiwi Syslog Daemon
. Kiwi CatTools
. Kiwi Secure Tunnel
. Kiwi SyslogGen
. Kiwi Logfile Viewer
. Kiwi Logger

» other useful softwares and readings can be found on the kiwisyslog links page.