Customized Linux Classes

Over the last year we have been working with a large company that is moving all of their servers from Microsoft to Linux, specifically CentOS. This is an international company that is leveraging their growth by cutting costs on the server operations. Cost cutting was not the only reason they selected CentOS as the operating system, it was also based on stability and security. Down time for this company, as with most companies, is not an option, therefore stability is a major consideration. When approached by this company they had specific requirements for training all of their administrators and engineers. Basically, their entire server support staff were without Linux knowledge with little or no experience. No doubt moving an international company to Linux in one year is a major undertaking.

We took the specific requirements that they had for their administrators and built a curriculum from information that we had and based on special needs they requested. At that point we created an evaluation class held as a virtual class that students could log in and interact in the class with an instructor using VOIP and web conferencing tools. This process allows an instructor to talk, interact, demonstrate and actually access student desktops to help them with the labs.

Evaluation Class

The initial class of 25 included those who would adjust the content so the company could allow students to be trained in 30 hours instead of the standard 40 for Linux Server Administration. This allowed for two, 3 hour sessions each day with a 2 hour break in between. A unique way of providing training to provide optimum learning for students. We provided a 500 page manual for each student as well as 200 videos for students to review online if they needed additional help during or after the class. Each student had a virtual CentOS server provided to them so they could use a CentOS server during the class on their Windows desktop. The instructor discussed a topic, illustrated it and then had students perform one of 175 labs that we provided for CentOS. The focus was on instruction followed by application and interaction with the student.

Additional Linux Classes

At this point we have been providing monthly classes for students in the organization for almost a year. Classes have been live Linux training on location and live Linus training using the virtual desktop. This kind of flexibility allows the company to choose the delivery method that best works for the students. It also provides flexibility because of the International aspect of this company as they have offices most major world countries.

The live online training provided access for students in any country and times for classes were modified so that it was more convenient for students. Our instructors started virtual classes day and night providing any time request made by the company. All of these factors in Linux training demonstrate that live training can be provided internationally with live classrooms on a virtual desktop or instructors can physically be where a company needs training, meeting the needs of companies migrating to Linux.

The Ubuntu server is the most innovative distribution for servers. It enables administrators to gain access to cutting edge technology and implement that with new ideas. If you are looking for the latest and greatest, this is the server option for you.

Focus: rating 9
The Ubuntu focus is to provide an Enterprise level server that is cutting edge in technology and innovative in ideas doing this all with an interest in simplicity. The stated goal of the Ubuntu Server Team is “working on simplifying the system administrator’s life, while focusing on advanced features, rock-solid stability, and high performance”(https://wiki.ubuntu.com/ServerTeam/).

Source: rating 9
Debian was the source of the Ubuntu Server but in time, the distance between these two have increased as innovation has brought new ideas and technologies to Ubuntu. The distance is also created by Canonical’s determination to make two releases every year, on time no matter what. At this point Ubuntu is independent in terms of where it is going and so has no real dependency upon any other distributions and their development. Having a history rooted in Debian’s huge application base fits well with the Ubuntu Server focus and has brought many experienced administrators from the Debian camp to show interest in Ubuntu.

Stability: rating 8
Stability is based upon a user base of installations that provide feedback as well as a determined testing cycle. Unfortunately, Ubuntu cannot be cutting edge and innovative and be as stable as administrator’s would like. The biggest negative feedback that I have received from administrator’s who run Ubuntu in production environments is the number of bugs that seem to creep into the system. If you are unwilling or unprepared to solve small bugs on a regular basis, choose another distribution. Now, not to say that Ubuntu is not stable, it is, but you will consistently be nagged by small issues. The 6 month release cycle does not contribute to stability, other distributions like Debian and Red Hat have learned that.

Security: rating 8
Security and stability work together. As an administrator, you may be concerned about the small bugs and what they do with security. That is certainly something to consider. Again, Canonical cannot provide innovative ideas and hardware device drivers that are cutting edge and at the same time provide the highest level of security, it just is not possible to have both worlds. Developers have tried to implement security principles like logging into the system as an unprivileged user. Complex aspects of security that an administrator may choose like SELinux and ACLs are available but not installed by default. If your organization wants to employ SELinux choose CentOS/RHEL which is designed from the beginning for that purpose.

The Uncomplicated Firewall is designed to be an easier way to manage a firewall from the command line. Unfortunately it is not activated on start up so your server has no network protection initially. The Ubuntu 9.10 server brings three new features to the UFW firewall; outgoing filtering update, filtering by interface and bash completion. This now brings a total of 12 new features since the UFW was first released in version 8.04. Finally, the UFW is reaching a mature stage where you can use it instead of writing rules with iptables. This is a good example of an innovative security option that adds value to the system but was in an immature state for 2 years as it developed.

AppArmor enables protection against those zero day bugs, which is great but, AppArmor has several serious issues. First the future is in question for this application as the developers now work for Microsoft and second, AppArmor requires a creation of a security profile for each application. This creation process is limited by the amount of time an administrator needs to use to implement the application and will never be system wide in scope like SELinux. That said, more profiles are available all of the time.

Blocking the loading of additional modules into the kernel after boot is a security feature added to Ubuntu server among many others.

Cost: rating 9
Access to the install CD and repositories of course is free. Documentation from the community is better than most distributions. Ubuntu as a whole has a fabulous community and they are known for their contribution to documentation and forums. However, any consideration of cost must include the cost of solving small issues that arise with cutting edge software so be prepared to allow administrators time to work with these issues. Also, consider Ubuntu training options for administrators to enhance their ability to understand the Ubuntu system and how to use it effectively.

On the flip side of the coin, developers have been true to their goal of making the Linux server easier to deploy. Without actually installing a wide range of Ubuntu servers you would not be able to understand the hard work that has gone into the Ubuntu server config files. For example, when you install Postfix mail server the default configuration already has keys and TLS set up to make your work a little easier. These innovations are small points that Ubuntu servers do not always get credit for and they certainly will save an administrator time.

Features: 10
In terms of available features Ubuntu servers certainly are rated 10 for ideas that you may want to deploy like, Cloud Computing. The Ubuntu server supports the latest apache, MySQL, PHP, FTP, etc. This distribution is an excellent choice if you need cutting edge versions. Again, what Ubuntu gives up with security and stability it makes up for with features and versions.

JeOS provides a version of the Ubuntu server that is created for appliances. This provides an efficient way to use technology on those lightweight devices that so many organization depend upon.

Landscape, for a fee, allows you to manage a large number of servers from one location.

Ease of Management: rating 10
The use of apt-get is legendary and is a great tool for management. Innovative additions to applications like the configuration offered for Postfix make administration easier and installation process provides simple ways to install applications with security enhancements like MySQL, PHP and apache. Overall, management of the Ubuntu server is made easier by the concepts built into the server install.

Support: rating 9
Support provided by the community in bug reports, forums, and documentation cannot be beat by any distribution. Commercial support is provided by Canonical for those difficult issues that you may be facing.

Summary:
If you are using the latest hardware or if you want cutting edge technology supported by innovative ideas, Ubuntu server is the choice for you. One of the reasons we provide Ubuntu server training is that it provides a real contrast to that of CentOS.

Evaluating the CentOS Enterprise Server
There are a number of popular choices for Linux enterprise level servers including CentOS, Ubuntu, Debian, Slackware and others including Red Hat Enterprise. This series of articles on a choice for a Linux Server will compare several of these Linux distributions to examine the advantages and disadvantages of each distribution. What is important to recognize in this evaluation is that how you view advantages and disadvantages are dependent upon the expertise of your Linux administrators and the level of support you need to maintain your servers.

How to Evaluate Enterprise Servers
There must be criteria for evaluating enterprise level servers to make the comparison. In this comparison, each distribution has a focus or philosophy which drives them in a specific direction and influences package choice, package versions and hardware support. The first evaluation examines CentOS as an enterprise level server.

Focus: rating 9
The primary focus for CentOS is to provide a stable and secure community version of Red Hat Enterprise by building the distro from the source code of RHEL. The emphasis on stability comes from longer testing of packages, conservative choices on versions and avoidance of cutting edge versions. The emphasis on security comes from the years of hard work that have gone into the development and application of SELinux. Though the focus on stability and security is a top priority for this distro this rating is not a 10 because of an increased interest in adding Desktop options to the packages which are in contrast to the primary goals.

Source: rating 8
CentOS is built from the source code of Red Hat Enterprise. For the most part these distributions are very similar. However, one of the criticisms of CentOS has been the delay of release versions based on the fact that Red Hat releases their source and then packages need to be modified to create the version for CentOS. The time delay has been a contested issue. The delay can be as much as 2-3 months which makes many people nervous about the future of the project. You need to recognize that the developers need time to make the transition to the new version and must do testing to verify the integrity of the version change. If you are looking for a Red Hat type distribution and need updates to versions immediately, you need think about purchasing from Red Hat.

Stability: rating 9
Stability is directly related to user base, choice of applications that are included and rigorous testing. The larger the user base the more likely you will discover issues so they can be resolved. CentOS has a huge user base, the exact numbers are very difficult to estimate. I would venture to say that CentOS has the largest user base outside of RHEL. The stability of CentOS is legend as it basically follows the path of RHEL in terms of package selection and testing. If you can live with the limited packages that are available in the repository, you will find that the stability is indeed rock solid. If you find yourself adding repositories that were not tested with the base system, then you will certainly see a loss in stability.

Security: rating 10
Security of course is directly related to stability. If your system in unstable it will certainly lead to security issues. CentOS contains a number of important security features. The most powerful feature that it employs is that of SELinux or Security Enhanced Linux. This powerful features provides realtime protection and limited liability if there is a compromise. That said, the majority of administrators turn SELinux off as it is difficult to manage, in their opinion. If you turn off SELinux, you are downgrading your system security, especially as SELinux is the future for RHEL and will continue to be a focus. Other important security aspects are Access Control Lists (ACLs) that are standard in CentOS. ACLs will help minimize the need for applications that have write permissions for others and provide the administrator with granularity for file permissions. Encrypted Block devices which were made available in version 5.3 also provide a standard option. You can now encrypt a block device, a hard drive or partition, so that when the block device is not mounted it is encrypted, a very nice standard option. CentOs comes standard with an iptables firewall frontend called lokkit which is easy to use but not really an enterprise level firewall.

Cost: rating 10
Cost is not only measured in the amount you pay for the code, which in this case it is free, but it is also a measure in available documentation, bugs that must be fixed and ease of management. CentOS rates high in all of these aspects as there is sufficient documentation, it has limited bug issues and management is reasonable if the administrator is trained. The level of CentOS Training of your Linux administrators is critical in understanding the cost. Just because you can install a Linux distribution for free does not mean in the end it will be cheaper that paying for licenses if your administrators do not have the skills needed to manage the server.

Features: 9
CentOS contains all of the necessary features for an enterprise level server like; apache, MySQL, PHP, vsftpd, sendmail, etc. These applications work well together and are stable. However, you will see a frustration among users based on the version of MySQL or PHP, etc. because these versions are somewhat behind the cutting edge. This is a result of the focus on stability and security. What this means for your organization is that if your software runs only on a specific version of software that is not standard to CentOS, you should evaluate this issue closely. The features are there if you can live with the versions.

SELinux – Though SELinux is often turned off by administrators, it is a major feature of CentOS. In order to use SELinux basically the entire operating system needs to be modified to add these file extensions. SELinux is the focus in terms of security for this distro. If you want to use SELinux Centos or RHEL are the only real options as the other distros only use this as an add on feature which means it will have limited usability on those distros. Creating better tools and making management of SELinux easier are under development.
Software RAID – Software RAID is a useful option and is to the point of being faster than some cheap hardware RAID, so this is solid feature supporting the major RAID levels.
Logical Volume Management – LVM will certainly be a necessary component of any Enterprise level server and CentOS has standard support for LVM2.
Access Control Lists – ACLs provide an important tool to manage file permissions based on user access. This is a default aspect with CentOS.
Block Encryption – Since version 5.3 you can use block encryption to secure partitions and drives.

Ease of Management: rating 10
CentOS uses the yum package manager and is an excellent tool for updates and installing applications. The advantage of yum is that it not only connects with the repository for the application you want to install but it also discovers and installs needed dependencies. The daily management of the system is straightforward.

Support: rating 7
Support for CentOs is based upon forums, documentation, and Google searches. The CentOS site link for commercial support is empty. The important point here is that you need trained administrators to manage these systems as you cannot call CentOS for a solution although CentOs support is available for a fee from a number of sites. Because of the huge user base there is quite a number of blogs, posts, etc. that help you solve problems.

Summary:
If your focus is on stability and security for an enterprise level server CentOS is a great choice. If you need cutting edge hardware drivers and the latest versions of software, you may have to look at another Linux distribution like Ubuntu. Primary to any choice is having skilled administrators in charge of your enterprise server.

Interested in Linux training but not sure which package bests fits your needs? Our Personal Preview will provide you 20 minutes with an instructor to review your needs and examine the manuals, the labs, watch sample videos, and examine the web interface for access to the training.

The Personal Preview
The Personal Preview is designed to help you examine your needs and review the options that best suit your Linux training future. Since we work with many of our students one-on-one this allows us to customize options for you.

We will be pleased to provide you with a 20 minute preview of any of the following products:
1. CentOS Live Server Course
2. Ubuntu Live server Course
3. Postfix Mail Server Course
4. Nagios Monitoring Course
5. Server Virtualization Course
6. Online Ubuntu Server Course
7. Online CentOS Server Course
8. Online Apache Security Course
9. Online Bash Shell Scripting Course

The Personal Preview works like this:
Request a Preview
Send and email to mweber at spidertools.com and include your name, return email and the class that you would like to preview. Also include a convenient time. If you have multiple staff that want to attend the Webinar let us know so we can provide that access. We will respond within 4 hours typically depending if we are training at the time of the request.

Receive a Webinar Link
We will send you a login to a Personal Webinar so that you can talk with an instructor, view videos, examine the manuals and basically ask any questions that you may want to ask. The whole process will take about 20 minutes.

Mike Weber
President, CyberMontana Inc.
Box 1262
Trout Creek, MT 59874

The process of class evaluation for an on-site training option involves three steps that aid in creating a more effective class each time it is presented. Those three steps are instructor evaluation, update training material and create new training material.

Instructor Evaluation
We provide instructor evaluation options for students so we can gain feedback on the class and discover where we might improve training options as well as which options work the best. There is always a great deal of subjectivity in any kind of evaluation so that must be taken into account. Really, all you can do is look for patterns. If the whole class says one thing then it is certainly true and needs to be taken into account whether it is good or bad. In reality, a good instructor should be making personal evaluation daily on how well students are receiving and absorbing information. Body language, participation, questions asked and outside discussion with the instructor are all ways for an instructor to do self-evaluation.

Update Training Material
The greatest advantage of writing your own training material is that you can always evaluate and modify the content on a regular basis. We try to make changes to training material monthly so that it is always fresh and up to date. This means that the manuals are printed just before classes to reflect changes made from the last class. We have recently recreated a Learning Portal that we can use to provide access for students to receive additional information after class as well as newly developed videos which we provide. We currently have almost 150 videos for the Linux Administration Classes. This is a create way to support students and organizations after class as all of the newly developed documentation and videos will be accessible to students for 6 months.

Create New Training Material
One of the aspects I do after a class is introduce any changes or new material into the manual for the next class. During this class I created several new images, and slides so those will be introduced into the next class. One thing we try to pay attention to is how well Labs went as Labs are the key to learning and development of skills. Typos, no matter how hard to pursue them are always an issue that needs to be addressed.

Class evaluation is a major part of making classes more effective and updating the content to be relative to student needs.

Day 4
This series of blog posts demonstrates many of the topics and issues that occur with On-Site Linux Training. The importance of the last day is not only that you cover the scheduled material but you put into place communication options for students after class, cover any questions that students may have often adjust the class content to any special needs that students may need. In this training session one of the requests by the class was to minimize security training and focus more on server performance issues as they had more responsibility related to that topic.

Content for the last day covered VNC as a method of connecting to the server both within the network and also connecting over the Internet. It is important to communicate the issue of security when using VNC as most client-server connections are not encrypted so you want to point out the clients that do provide encryption. Speed is also a important problem, especially on Internet connections. In class, the Lab always encourages students both to login with TWM which is a minimized option and also the full Desktop which is convenient but neither necessary and certainly slow.

SSH is the major focus for remote server administration as it is encrypted and fast. However, many administrators moving from a Windows background are looking for an graphical option like VNC despite the issues of speed and security. It is imperative that students can use SSH in both logging into a server, transferring files and using graphical tools like Filezilla to connect on port 22 so that if they have to move files from a Windows machine they are capable of transferring files.

The Performance issues evaluate 5 things that can be bottlenecks for Linux servers. Disk usage, I/O, CPU, memory and networking are all evaluated on how you might tune these options for better server performance.

Once the training is complete one of the things that we try to maintain is communication and continual training after the class. We always provide email and contact information if students have questions. But we also provide a unique service in that we provide students a login to our portal where we provide updated content in the manuals that are constantly updated, updated VMWare images for students to download and Flash videos with voice so students may watch class topics online to continue their training. This is critical for continual training as students cannot absorb all of the material when it is presented.

The second day was built around building partitions and configuring LVM, while this day is focused on using multiple RAID options and explaining principles for choosing RAID options. Even using VMWare with a virtual machine it is a great way to teach students how to configure with software RAID. We create RAID 0,1 and 5 and also discuss other newer options like RAID 6, 10, etc. The key to learning software RAID is to build it on a virtual machine with multiple virtual drives. Once students create RAID 3 or 4 times it is going to stick with them. We also talk about the differences between using hardware RAID and software RAID as well as practice breaking and fixing RAID.

The afternoon provides students options for backup using tar, rsync and dd. This basic tools can provide system backups or provide options for user level backups. Basic scripts are written and tested during these Labs for the use of backups. Automating actions are important time savers for administrators so we examine at and cron for students to use in automated activities. This information on backups, scripts and automation is applied when we look at SSH as an option with passwordless backups on the next day.

It is amazing to me how many students struggle with SSH as most students are Windows administrators moving to Linux and are not command line comfortable. SSH is one of those key features in understanding and performing Linux administration. With the remote skills of being able to use SSH and administrator can basically be anywhere to work on a remote server.

The second day of an On-Site Training Session is the day that students recognize how challenging the process will be to learn Linux Administration. The first day is always filled with expectation and it is tough when that expectation and desire looks reality in the eye. This is an issue in training that you have to approach from a position of facing the training as a challenge that must be taken one step at a time. Linux Administration is a process that involves thousands of details that are not intuitive because you are working with a command line not a GUI, you are working with commands that are strange but powerful and you are trying to figure out a file system that is like nothing you have seen before. As an instructor the goal of the second day, is not only presenting the challenge to students but helping them take a foothold in the learning process to bring a light at the end of the tunnel. This can be accomplished with the topics on the second day which focus on managing users, quotas, managing system logs and using tools to manage your drives.

Managing users and understanding logs are two of the easier topics in Linux administration so students gain some confidence once they have been exposed to these topics. They enjoy the feeling of accomplishment and control they gain by mastering the fdisk command and building LVM partitions. For most students this is the fist time they have partitioned, formatted, and mounted a partition. This opens up new methods avenues of understanding for how the whole Linux file system works and how many options really exist. This is the source of hope as they recognize that becoming a Linux Administrator is possible.

This day is a day of interest as most students do not know how to build hard drives using fdisk, LVM or RAID so spending a step-by-step process for most of the day breaks new ground for most students. We purposely build and dismantle LVM correctly 6 or 7 times and have them mount the partitions on the file system. The virtual machines that we use have one drive with the file system on it and one drive that is completely blank. This allows us to have students do all of the building on one drive without as much chance they will make a mistake and break something on virtual machine. We build everything from the command line and also spend some time looking at the graphical tools for managing the LVM, pointing out bugs with the graphical tool.

When presenting difficult material like partitioning drives be careful in the speed at which you cover the topic. Students will not always let you know that they need a slower pace so it is important that you recognize warning signals. Those signals are often when one student is helping another…or if you sense frustration in the questions asked…if you see that recheck to verify the pace you are using in progressing through the material.

Reality Check….Linux Server Administration is a challenge that must be taken on one step at a time.

The first 10 minutes of an on-site class is crucial. I usually have three goals. First, try to demonstrate that you are capable as a Linux instructor. You can do that by avoiding talk about certifications, experience or the classes you have taught. Instead, have well organized and good looking material. Have your presentation material up and running smoothly before the students arrive. Strike up conversations and present yourself as a regular person. And yes, though I hate “dress for success”, you need to look like you to are personally organized. What you project with your material and appearance is what they will project for the actual class and what they expect to learn. Failure in the first 10 minutes is hard to recover from.

The second thing I try to convey in the first 10 minutes is that I really care about helping them learn. This particular day I told the class I would stay in the classroom for lunch so they could ask questions outside of class. I always make it a habit to be early to class as well, again providing extra access so students know that you care about the fact that they are in a learning process that is difficult. Provide them outside resources like supportive videos, updates to documentation and your personal email and contact information. Of course, there is a limit to access outside of class, but making some effort here goes a long way.

The third thing that is important initially is to layout the format of class, how will the class work. So I provide a basic schedule that they will get Labs and opportunity to move around at least once an hour. Listen to suggestions of the students and scheduling options like when to have lunch as these are important to them.

I always emphasize the importance of students asking questions and reinforce those who do so you can progress in the class so students feel comfortable asking questions in front of others. Students often are not supportive of each other so it is important that you support all students in the class to set the tone. You always have a situation where students are at different levels of understanding so it is important to move at a rate that challenged students can grasp the information but more advanced students are also showing interest. When companies create the training group they often do not think about this aspect so it is left up to the instructor to motivate and manage the class.

Topics covered the first day are an introduction into vi, the boot process, the root user, and process management. It is important to verify students can effectively use a text editor like vi or nano since all of the real work on a Linux server will be done at the command line. Labs to reinforce text editing, searches, text replacement and movement are critical. It seems logical to start with the boot process after an introduction. In reality it is a challenge to bring the boot process to a level everyone can understand. However, Labs really break the ice and help students get into the course. Most students really do not comprehend the power and danger of the root user, especially in terms of making mistakes and security. Having students work in the class as root and make mistakes that cost them is important on the test server they work on so these issues start to sink in. Managing processes is all about the server performing at the level the company requires. Killing unruly processes and restricting processes is an important aspect of learning system administration.

All around the first day is an important day to set the standards for the teaching, the style of teaching that works in communication and relating to the students as an instructor. Linux training is both challenging and rewarding. What you do the first day sets up the second day which will we talk about in the next entry.

When you travel to a site to train, you will be somewhat at a disadvantage. You are the one who is tired, the one who is sleeping in a hotel and eating food that is not the greatest. So, you need to take some steps to prepare yourself to overcome the disadvantages that you face. On-Site Linux Training certainly poses several challenges that you do not face when students come to you in a virtual class or a class at a location where you do not have to travel.

Use your time wisely. It is easy to waste your time watching TV when you should be reviewing your material or making adjustments to your presentation material.

Set a schedule. One thing I found while traveling is that setting the same time I go to bed, get up, go for breakfast, all of those things help when you are on the road. You have enough changes already, setting patterns for your sleep and eating habits will minimize the impact.

Boost your immunity. Travel can be difficult as it disrupts your weekly schedule, exposes you to countless wasted hours and brings you in contact with lots of people who could make you sick, think Swine Flu here. Usually you do not think about think about the chances of getting sick from a trip but with all the news about Swine Flu, it makes you a bit paranoid. In fact, once you get sick on a trip, you probably will not forget it and you will take extra precautions for future adventures. It is certainly disruptive to any process where you are trying to train or learn. One of the things I do is to take Airborn twice a day during the trip and several days after. Airborn boots your immunity for a short time with extra vitamins.

Keep up with work. It is easy to think you are on a vacation when you travel, but it is not the case. You need to do as much work as possible while on the road instead of leaving it to be a mountain when you get back. Not easy to do but you will certainly thank yourself on the Monday that you return.

Make connections. One of the major advantages of travel is that you can make connections with people face-to-face. Use that to your advantage, spend extra time with students outside of class if possible to build relationships for business in the future.

Get a perspective. When you travel to a location to train, you will have the advantage of gaining a unique perspective about the company you are training for. You will gain insight into the IT department and how they work with their Linux administrators. These insights about the company may help you train more effectively. For example, what resources do administrators have on a day to day basis after the class. You will be able to aid students in finding good resources or provide additional resources for students. One of the projects that we have done is to begin a complete video database online for students that contains the class information so they have that resource to refer to a later.

There are many advantages of traveling to a location to train, but the advantages do not come automatically, you will need to take steps to make them work for you.