Oracle related rants (and lots of off-topic stuff)…
Lenz Grimmer blogged today about the release of the “oracle-rdbms-server-11gR2-preinstall” package, the Oracle Linux 6 version of the “oracle-validated” package we know and love.
I did a run through of an installation using it and it does exactly what it says it will. I’ve modified my 11gR2 installation on OL6 article accordingly.
Cheers
Tim…
I tend to self host as much as possible, so the emphasis is always on me to keep on top of my backups. Like most DBAs, I’m a bit of a control freak, so relying on myself suits me. Having said that, there are some services I delegate to the cloud (mail, contacts, calendar). Yesterday I was thinking about how bummed out I would be if any of these services lost my data and I suddenly got the fear. This morning I’ve had a backup frenzy. The following notes from Google give suggestions for backing up mail, contacts and calendar entries.
I was wondering how many other people bother with this? Do people even consider the impact of a goof-up by their online mail provider?
Many moons ago I used to use Blogger and I used to export my posts on a regular basis. There are some awesome blogs out there and the thought of them being lost is a nightmare. I remember Mark Rittman had a problem with his blog many years ago. Are people who have blogs hosted by Blogger or WordPress bothering with backups?
So now I’m feeling a little more secure as my PC, NAS and Google will need to go bang for me to lose my data on the cloud.
Cheers
Tim…
PS. Notice how I managed to mention cloud a few times. Gosh I’m so relevant! 🙂
Over the last few months my browser usage switched from pure Chrome to a combination of Chrome, Firefox and Opera, all running on Fedora 16 (x86-64). This may sound a little odd, but when you see what I use them for it may not sound so wacky.
So now I’m a triple-browser guy. 🙂
Interested to know:
Cheers
Tim…
Update: Colin ‘t Hart mentioned the Incognito Window in Google Chrome. It does seem to give the correct (non-social) serach results, but it is a separate window, so not sure if it is a better approach than running Opera. Kinda like the complete separate of running Opera, but worth thinking about though.
One of my friends used to own a sandwich bar. He knew the exact profit margin on each product. He knew the impact of a price change from one supplier on each of the products he sold, as well as the overall affect on his profits.
So compare that situation with your average IT department, where to be frank, nobody has a bloody clue about costs. Yes, we all know the headline grabbers like licensing cost for Oracle and you can probably find the bit of paper that tells you the yearly hardware maintenance fee, but I’ve not encountered many companies that have a handle on the real cost of projects. If a company can’t say, “Project X cost £Y to complete and costs £Z a year to maintain and this is the breakdown of costs”, with a reasonable level of accuracy then they’ve failed.
You need this sort of data in order to make a valid judgement about new projects. When someone starts extolling the virtues of the latest and greatest database/language/framework, how can you make a judgement on the relative savings you can make if you don’t know your true costs? Free software is not free if you have to pay people to integrate it into your existing systems and hire/train staff with the relevant skills. Conversely, paying ridiculous licensing costs may not be sensible compared to hiring/training skills to allow you to use cheaper alternatives.
I sometimes feel the IT industry is like some cowboy building firm. When someone asks for a price you scratch your chin, suck in some air then pull a random figure out of the ether. Don’t even get me started on the sales people, with their astronomical list prices that nobody ever pays, just so they can make you feel like you’ve got a “good deal”. It’s an industry in dire need of a change.
[/RANT]
Cheers
Tim…
I’ve just put another batch of Linux articles live.
As before, they are focussing on the RHCSA exam objectives, so a lot of it is pretty basic information.
The Firewall and SELinux objectives are the only ones left now. These two objectives were the main reasons I decided to start this process. I left them until last because I figured if I started with them, I might never get round to doing the other articles. 🙂
As far as the Linux firewall goes, if it can’t be done with the point and click GUI (or TUI), I don’t do it, so taking a look at iptables from the command line has been on my list for a very long time. The RHCSA objective suggests using the GUI/TUI interface should be sufficient, since it says, “using system-config-firewall or iptables”. In contrast, the RHCE objectives explicitly mention iptables, possibly suggesting tasks that may not be possible from the GUI? The question is, how much do I trust my own judgement on this matter? I would prefer go in to the RHCSA exam with too much information, rather than not enough, so I guess I’ll take a look at iptables from the command line before attempting the RHCSA exam.
I know even less about SELinux than I do about the firewall. For Oracle installations I typically disable it. 🙂 So I guess this objective is going to be a magical mystery tour. 🙂
If anyone has sat the RHCSA exam for RHEL6, I would be interested to hear your thoughts on the Firewall and SELinux objectives. I think I’ve got a pretty good handle on the other objectives, but I’m kinda shooting in the dark with these two. It would be a shame to waste £400 on a failed exam. 🙂
Cheers
Tim…
I can hardly believe it. It’s finally happened!!!
Check out the story here.
The certification matrix on MOS is not updated yet, and those on RHEL kernel will have to wait a few more days (90), but at last we have some firm commitment. 🙂
From now on, the Oracle Linux errata are available free from http://public-yum.oracle.com. In the past only the updates (5.6, 5.7 etc.) were available. This makes OL even more useful than before.
Thank you!
Cheers
Tim…
Update: Remember, if you apply the errata to OL6.2, you will have the same scsi_id issue I saw with 5.8.
All The Rage is the fourth book in the Repairman Jack series by F. Paul Wilson.
There is a new designer drug in town. In the right dose it makes you assertive and confident. Too much and you become a savage killer. What seems like an innocent case for Jack, turns into a life or death situation for him and the people he loves.
A pretty neat romp that follows on quite nicely from the previous books…
Cheers
Tim…
Followers of this blog, Twitter or Google+ can’t help but have noticed me moaning about my hosting provider (Fasthosts). My site was moved on to a new server (by accident) in December:
Since then I’ve been having assorted rants on G+ and Twitter because the site has been up and down a lot.
I started looking at new (UK-based) hosting providers, but the reviews of all of them are pretty terrible. Part of this is because they are all pretty dodgy, having to cut so many corners to make a profit, and part of it is because people (like me) only tend to review things when they are really bad. So here I was, caught between a rock and a hard place. Stick with Fasthosts (who I’ve been with for 11 years), or make a move?
Whilst looking for a new hosting company, I continued to hassle Fasthosts, opening tickets for every failure and providing all sorts of tracing, screen shots. Eventually, they offered to switch me to another server. On Thursday night (about midnight UK time), the server move was initiated. I spent until 03:45 snagging the move, then went to bed. I woke up to a message from Arjen Visser from Dbvisit.com saying there was an issue with the site. By the time I picked up the message things were working again, so I filed this as a “bedding in” issue. 🙂 Later that day, there was one 15 minute downtime, which I logged and was given a proper explanation for by the support team (the first so far!!). Since then, as far as I know, the site has bee working fine. Fingers crossed.
I pay yearly, so I’m paid up until December, but I’m going to continue to investigate other hosting options, just in case this all kicks off again. If anyone has any long-term experience of a UK-based hosting provider I am interested to know. One of my friends recently moved to 1and1.co.uk, who have pretty terrible reviews, but so far he’s having a good experience. I’ve done a bit of system admin for him and so far there has been no drama.
Cheers
Tim…
I just did an update from Oracle Linux 5.7 to 5.8 on one of my VirtualBox RAC installations and things are not looking to clever at the moment. After a reboot, the ASM instances and therefore the database instances wouldn’t restart. A quick look showed the ASM disks were not visible. On this installation I was using UDEV, rather than ASMLib. In checking the UDEV rules I noticed the scsi_id command on OL5.8 doesn’t report an ID for partitions on disks, only the disks themselves. For example, on OL5.7 I get this,
# /sbin/scsi_id -g -u -s /block/sdb/sdb1 SATA_VBOX_HARDDISK_VBd306dbe0-df3367e3_ #
On OL5.8 I get this,
# /sbin/scsi_id -g -u -s /block/sdb/sdb1 #
If I run it against the disk, rather than the partition it works fine.
This has literally just happened, so I’ve done no further investigation, but I thought it was worth putting out there in case anyone was about to start an OS update on something they cared about. 🙂
At this point I’m not discounting that I’ve screwed up somewhere. My next plan is to install three clean VMs (OL 5.6, 5.7 and 5.8) and check the output of scsi_id on each of them. If that turns out OK, then I’ve screwed something else and you can probably ignore this post. I might not get to try it out until tomorrow. Either way, I’ll update this post with the results of that test.
Cheers
Tim…
Update 1: It’s definitely changed. See the following.
# cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.6 (Tikanga) # /sbin/scsi_id -g -u -s /block/sda/sda1 SATA_VBOX_HARDDISK_VB54dff07f-931ce4d7_ # # cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.7 (Tikanga) # /sbin/scsi_id -g -u -s /block/sda/sda1 SATA_VBOX_HARDDISK_VBx180d717-f896e661_ # # cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.8 (Tikanga) # /sbin/scsi_id -g -u -s /block/sda/sda1 #
Update 2: As John Sobecki correctly pointed out in the comments, the title of the post is misleading. UDEV is not at fault here. The problem is the “/sbin/scsi_id” command is behaving differently, which is making my rules useless. The UDEV issue is the symptom, not the cause. The post is clearly focusing on the scsi_id issue, but I’ve picked a pretty bad title to go with it. 🙂
Update 3: John Sobecki pointed me at “[block] fail SCSI passthrough ioctls on partition devices CVE-2011-4127”, a mainline kernel security fix that seems to be the cause of this. It affects all new kernels which include this change (RHEL5/6, UEK etc). Oracle are testing the impact of this. Initially ASMLib and OCFS seem unaffected.
Update 4: MOS Note 1438604.1 (currently in review) contains more information about this issue. ASMLib and OCFS are unaffected by CVE-2011-4127, so ASMLib should probably be used in preference to UDEV with newer kernels.
Update 5: I’ve altered all the articles on my site to reference the parent (disk) device, rather than the partition device, which makes the UDEV rules work fine again. Thanks to Bryan Wood and Joachim for their suggestions.
A couple of weeks ago I wrote about my invite to the University of Birmingham CS Alumni Dinner, which took place last night…
It was really weird being back on the campus after all these years. I finished my PhD about 18 years ago (or something like that) I popped in to my department (Biosciences) a couple of times soon after I left and I used to train at the University gym for a little while, but it must be over a decade since I’ve been back. I don’t know about the rest of the campus, the part where I spent most of my time as changed a lot. Very freaky. 🙂
I wasn’t really sure what to expect from the evening, especially since I wasn’t a Computer Science graduate, but it turned out to be really good fun. I think I gave a number of people a repetitive strain injury (RSI) of the ears with my constant gabbing. I hope they found it worthwhile. I know I did. It’s interesting speaking to the next generation of computer geeks and trying to get a handle on what they think about the industry.
With a bit of luck I will get to do it all again next year. Hope so.
Cheers
Tim…