PXE Installations on RHEL6 / OL6

I spent yesterday neatening up a few old articles. For the most part it is a bit of a dull process, but it has to be done every so often.

With what’s going on at work, it seemed like a good idea bring my old Kickstart and PXE Installation articles up to date. My kickstart article was written in the RHEL3 era which needed bringing up to date. Nothing has really changed about the process, but some new screen shots from OL6 make it look a little fresher. My old PXE Installation article was written against RHEL5/OL5, so I figured things wouldn’t have changed much between that and RHEL6/OL6… Wrong! I ended up having to write a new article specifically for PXE Installations on RHEL6/OL6.

I think that’s enough of me pretending to be a Linux sysadmin for a while… 🙂

Cheers

Tim…

All change. Virtualization, here we come!

Followers of the blog will know I dig virtualization. I first ran Oracle in virtualized environments over a decade ago.

In my current company there is a strong virtualization presence in the Windows space. Pretty much all Windows servers, including those running MS SQL Server, are actually VMs running on a VMware farm. The UNIX/Linux side is a little different. Most stuff is still done on physical boxes and what little virtualization is done, uses CentOS and KVM for freebie open source solutions.

There are a lot of architectural changes going on at the moment and I’ve been pushing *very hard* for a switch to the virtual infrastructure (VI) for all our middle tier servers and a few of our databases. It is looking very likely (but not guaranteed) that this will happen.

Q: What is the incentive to switch to a virtualized environment?
A: We have a bad spread of resource utilization at the moment. Some very big boxes doing very little work, but in security zones that are too unsafe to use them for other purposes. Other boxes will soon be maxed out because they have been used to consolidate services. What’s more, some of the servers that are used for consolidation have multiple, conflicting, installations on them which are already starting to cause administration headaches.

Q: How can virtualization help with our resource utilization?
A: Using a 12 core server with 60G of RAM for a little Apache reverse proxy is crazy. For the sake of resilience, we have multiple of these. That’s just the tip of the iceberg. Imagine adding those servers to the farm, carving out some little VMs and leaving all the rest of the resources to do cool stuff with. Sounds like a no-brainer to me. 🙂

Q: How can virtualization products ease our administration headaches?
A: By far the biggest administration headaches we are seeing in the middle tier relate to having multiple installations of products on a single machine. Doing upgrades and trying to remove old software can cause no end of headaches. Some of our old boxes have 30+ installations on them. It does your noggin in when you are trying to find out what is going on. You often spend much more time trying to identify which installation you should be looking at, than actually doing the task you’ve been asked to do. By moving to the VI we can add a greater level of separation between some of these installations, making life much clearer. Our current vision is one installation per VM. To upgrade we set up new VMs, migrate the services on to them and bin the old VMs. Everything remains clean and simple.

Q: What virtualization product should we use?
A: We have a big investment in VMware. There is a dedicated team who manage this infrastructure and know what they are doing. IMHO it is only Fear, Uncertainty and Doubt (FUD) that prevents other people in the company moving some or all of the Linux stuff on to that infrastructure. Oracle products are only part of the infrastructure, but we understand and accept the Oracle licensing, support and certification implications of this move.

Q: What version of Linux will we be using?
A: Oracle Linux! Yeah baby!

Q: So nothing can go wrong?
A: Don’t be stupid. We are bound to get some pain points, but I think it will be a fantastic move in the right direction.

So now all that remains is to get the final approval and start moving this stuff on to the VI. If this happens I will be ecstatic. If it doesn’t I think my tantrums-per-day ratio will increase, but I’m bottom of the food chain in the company, so I will have to do what I’m told. 🙂 Fingers crossed.

Cheers

Tim…

RHCE Certification Articles (continued)…

I mentioned in my previous post on this subject that I had 5 more objectives yet to cover. The articles for those objectives have now been added to the website.

That completes the set!

The articles for both exams are available here. I also have a page listing the objectives for both exams, with links to each of my articles that cover them.

Now I just have to find the time to prepare for and sit the exams… 🙂

Cheers

Tim…

UltraEdit on Fedora 18…

I was using UltraEdit 3.3 on Fedora 17 with no problems. After the upgrade to Fedora 18 it continued to work fine. Then I noticed there was a newer build of 3.3 on the IDM website, so I downloaded and installed it. Unfortunately, it didn’t work. I guess it was a later build for Fedora 17, not a new Fedora 18 build.

I dropped the guys at IDM an email and they did a new build straight away and it worked fine. This build is available from the website now.

It’s nice when people write cool apps and back them up with good service when you need help!

Cheers

Tim…

Fedora 18 : The winner is MATE (so far)…

I’m a few days into Fedora 18 and I think I’ve come the the conclusion that the desktop that best suits *me* is MATE. The journey to this point has been a rather long and meandering one. Let’s cut it short and start at GNOME2.

  • GNOME2 : I was happy and all things were good.
  • GNOME 3 (GNOME Shell) : When it became the default Fedora window manager I went with the flow and stuck with it for a few months. At the time I thought it was OK. I even wrote some posts saying I kinda liked it. After a while it started to get on my nerves and I switched.
  • LXDE : That lasted about 10 minutes. Nuff said!
  • XFCE : I stuck with this for quite a few months. It’s very simple and very quick. There are a few rough edges, but nothing that really made me squirm.

Once I installed Fedora 18 I felt like I needed a change. A quick return to GNOME3 convinced me that I now truly hate it.

  • Cinnamon : The first impression was very good. It’s not officially “supported” on Fedora, but is in the repo. The Fedora version seems a little buggy, which is where the problems began. I started trying to arrange my desktop and stuff just didn’t work. I have a feeling that Cinnamon may end up being my desktop of choice in the future, but for now I’ll have to pass for something that works properly on Fedora.
  • KDE : I’ve had brief dalliances with KDE over the years. The people who love it seem almost fanatical. Every time I’ve tried it, it has driven me nuts. I had made a decision that Fedora 18 was probably going to be the version where I become a KDE fan. Two days was all I could take. I don’t know what it is about KDE, but I can’t handle it. It is by far the prettiest window manager. I look at it and I feel like I want to use it. Trouble is, when I start I feel like it is getting in my way. I can’t really put my finger on it. It just isn’t for me.
  • MATE : So we come full circle. MATE is a fork of GNOME2. I read something recently that says it uses most of the plumbing of GNOME3, but has the “traditional” GNOME2 feel.  I installed it and it felt like coming home. After a few months of being out in the cold, MATE was a hot fire, a pair of warm slippers and plate of beans on toast with a bit of cheese on top. Fantastic! My desktop is very simple and functional. The interface does not get in my way. It’s not going to make Linux the desktop of choice, but I think a lot of long time Fedora users will try it and like it.

I understand that open source is all about choice, but it seems such a shame that we have so many talented people all working on different window managers, none of which quite hit the mark. It just makes you wonder what could happen if they all worked together. Of course, it would never happen, but you can dream…

If I’m honest, OS X is better than any of these interfaces. I think Windows 7 probably is too. The bonus with having your interface dictated to you is you just get on with things and make do. The Linux desktop is definitely a case of “Freedom is slavery“. Being the Linux fan I am, I will just have to continue being a slave…

I reserve the right to change my mind at any time, so when next week I’m telling you Windows 8 is awesome, so be it. 🙂

Cheers

Tim…

Fedora 18 : Upgrading from Fedora 17…

I’ve just got to the end of a real upgrade of a Fedora 17 server to Fedora 18. The basic process goes like this.

  • Download the Fedora 18 ISO.
  • Update your current Fedora 17 system by issuing the “yum update” command and restart once it is complete.
  • Install the “fedup” package. “yum –enablerepo=updates-testing install fedup”
  • Run the fedup command pointing it to the Fedora 18 ISO you downloaded. “fedup-cli –iso /home/user/fedora-18.iso –debuglog=fedupdebug.log”
  • Check for errors in the log and correct if found.
  • Reboot the machine and select the “System Upgrade” option from the Grub menu.
  • Wait!

The system came up OK after this, but there are some gotchas. The first thing I did on completion was to run a “yum update” and lots of things were broken. Why? Well, after a lot of messing around and manually updating individual packages I finally figured out:

  1. Google Chrome, Skype and VirtualBox were all holding on to F17 versions of packages so yum was not able to update them.
  2. I also had a bunch of packages from the RPM Fusion repository that seemed to confuse things. If you are using that repository I suggest you manually update it using these commands.

    wget http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-18.noarch.rpm
    rpm -Uvh rpmfusion-free-release-18.noarch.rpm

  3. The dropbox repository is failing, so add “enabled=0” to the “/etc/yum.repos.d/dropbox.repo” file.

So IMHO, when you are going to do an upgrade, I would advise to remove any packages that didn’t come from the Fedora repository before starting, or be prepared to spend a few hours cleaning up afterwards. If I had stuck to just packages from the Fedora repository I think the upgrade would have been seamless. As it is, it was a bit of a pain, but now it’s all good.

I think I will have a little rest before trying another. 🙂

Cheers

Tim…

Update: I just did an upgrade to another machine. By taking my own advice and cleaning up first it was really easy. 🙂

Fedora 18 and Oracle 11gR2…

After several abortive attempts I finally got hold of Fedora 18 last night. Those mirrors are getting a real battering at the moment. 🙂

The first job was to do a basic installation.

I’d seen a few things written about the new installer, not all of which were positive. IMHO the installation was a really nice experience. It is very different to previous installers, which probably freaks some people out, but I think it works really well.

Once the installation is complete it’s pretty much business as usual. You’ve got newer versions of most of the packages, but to be honest I don’t really focus to much on that. I just keep doing “yum update” every few days and work with what I’ve got. 🙂

One thing that did take me by surprise is how much a hated GNOME Shell. I’ve written several times in that past that I thought it was OK. It was my default environment for quite a few months, but after spending an extended period on XFCE at home and Windows XP at work, I can safely say that I seriously don’t get GNOME Shell. Fortunately, Fedora 18 comes with a whole host of window managers including GNOME, KDE, XFCE, LXDE, Cinnamon and MATE, so I’m sure you’ll find something there that you can work with.

The next job was to see if Oracle would install on it.

Every time I do this I think to myself it’s going to be the last time. It’s far more sensible to use a VM and install the database on a supported distro. Oracle Linux is free and a supported platform, so messing around with installs on a non-supported distro, like Fedora, really doesn’t make sense. Maybe this will actually be the last time. 🙂

So what next? I’ve got some physical servers running Fedora 17 as the host OS which will have to be upgraded. I think I’m going to play around with Cinnamon and MATE before I do that. If they don’t work for me it’s back to plain and simple XFCE for my window manager. 🙂

Cheers

Tim…

RHCE Certification Articles…

Just before I started my current job I was planning on doing the RHCSA and RHCE exams for a bit of fun. In preparation for that I started to write the revision notes for each of the exam objectives. I got to the end of the RHCSA exam objectives, then my plan kind-of stalled, what with starting the new job etc.

Over the Christmas holiday I got some time to start the notes for the RHCE exam. If anything, the syllabus for this exam is a little simpler as many of the sections follow the same basic format. This full list of RHCE exam objectives includes the links to all the articles I’ve written to cover the objectives. There are still 5 to complete, but hopefully I’ll get those done soon.

The new articles I wrote include:

Some of the existing articles on the site got some changes to reflect other objectives, including:

Remember, these articles are targeted specifically at the exam objectives, rather than trying to provide everything you need to know about the subject. In my opinion, some of the exam objectives are rather too simple, missing out the more interesting and useful features of the software. In some cases I’ve added some extra information beyond the objectives, marking it as not part of the exam, or linked or other articles that give some ideas of other uses.

Once I finish the next batch of articles, I guess I should consider sitting the exams. I’m pretty confident I could get through them now if I had access to my notes, but in the exam you just have “man”  and “info” pages, so I would have to commit some of the stuff to memory to get through them. Although I’ve been using Linux for over a decade, the fact I don’t do system administration on a daily basis means some of the more obscure tasks aren’t committed to memory.

It would be nice to get the articles finished and exams done before Oracle 12c is released, or I will be distracted for a while learning all that stuff. 🙂

Cheers

Tim…

UltraEdit 3.3 for Mac/Linux…

I’m now rockin’ UltraEdit 3.3 on my MacBook Pro and Linux boxes at home. A previous announcement suggested by this version the Mac and Linux versions would have caught up with the Windows version from a functionality perspective. I’m not sure if that’s true, but they are close enough for me.

The latest Windows versions is 18.20, which I use at work, but home is where the real magic happens. 🙂

Cheers

Tim…

 

Android Jelly Bean 4.1.2 on my Nexus 7…

I turned on my Nexus 7 last night and it asked if I wanted to upgrade to Android 4.1.2 (Jelly Bean). The install was pretty quick and went through with no dramas.

I’m not all that interested in the whole Android thing. To be honest, I can’t even be bothered to check the change log. It’s just an enabling technology for me, not something I’m passionate about. What I can say it that it has finally fixed the home page swivel issue. In case you hadn’t heard, the Nexus 7 automatically orientates the screen to whichever way you are holding it, except for the home page which always stays in portrait mode. Not any more. Finally it too can swivel.

I was never sure why this screen didn’t act like all the others, but it seems Google has responded to the criticism and sorted it.

Cheers

Tim…