My thoughts on life, the universe and beer

Was reading up on something regarding CentOS/RHEL and found this page

It has some nice explanations on some Apache 2.2 configuration variables….

Laters,
Finnzi

BAH!

I thought i had seen all the license hell one could see….but noooooooooooooooooooooooo…

A company i’m doing IT for bought a Timekeeping application. No problem. We bought a one user license to start with since the company we bought it from told us that it was nooo problem to add users later.

Yeah…about that. Few days later i was asking for more users. Sure! they said…..after banging my head against the table i ended up with buying a Pervasive PSQL Server V10, found out that i also had to buy a multi-user license from the makers of the Timekeeping application (which they never told me, i guess when i asked about what i needed i was not clear enough!:).

Well…the application it self is good and the support people are friendly so it was not end of the world for me……

Anyone knows some freeware backup application that allows live backups of Pervasive PSQL servers ?

Bgrds,
Finnzi

Howdy,

Was browsing the Red Hat website earlier and saw an ad that showed how you could replace a RAC with a RHCS setup (active/standby).

Customers that request a setup of an Oracle RAC cluster probably do not understand all of the work that goes into designing, implementing and working with it on a daily basis. They do not understand the redundancy setup. They just want close to 100% uptime (99.999%+) and are willing to pay for it.

I have done work on both sides. I have been around a Oracle RAC setup, and i have done some RHCS installations.

Both setups have a number of things that could be better, but both give a fairly good redundancy.

RHCS is a active/standby setup. The good part here is that you could have 2 nodes, one active for database X, and the other one active for database Y. Node 1 goes down, node 2 checks, and if it does not respond it fences the other node (fencing could be: rebooting the node through a iLO, RSA, shutting down the FC ports the node uses, etc). If fencing succeeds the node that is still alive takes over the resources. This takes about 1-2 minutes. You can have a lot of nodes in a RHCS cluster, and you can pretty much cluster anything.

1-2 minutes you say…..Having a database failover to a new machine, running consistency checks for the databases and be online in 2 minutes. 2 minutes to failover is a pretty impressive job. Sure, some transactions could have failed, but your DBA has been paged, the database is back up and running and if your applications are written correctly they should continue to run.

Oracle RAC runs each database on both nodes. That would be a active-active setup. That is also pretty impressive. Both nodes run the same databases, active sessions are failed over to the other node if a failure occurs. You can even add nodes to your RAC cluster to scale with the load on your databases. RAC could help you achieve 100% uptime and crazy performance if needed.

What i think that is missing from a RAC setup is fencing. RAC does not reboot node X/Y if it detects a problem. The nodes are supposed to withdraw them selfs, do not get me wrong, so far i have not had any problems with this setup. However i would feel a lot better if RAC would have fencing methods, and could reboot a node that is dubious…If the node is not working as expected, it should be rebooted and removed from the cluster without syncing data down to disks etc. I am pretty sure the people at Oracle are very intelligent and have no doubts that they know what they are doing. I am just a very “careful” person and i think the RHCS does a bit better when it detects a failure.

RHCS is a very advanced tool, and when used correctly with a redundant SAN configuration you can achieve 99.999% uptime (around 5 minutes of downtime per year). If you do not need to scale your Oracle databases to 2+ nodes in a active-active configuration choose RHCS over RAC. It saves you a whole lot of money, and is very well supported. Management is (from my perspective) a lot easier and adding new databases, storage etc is no issue.

I bet i sound like a Red Hat sales person, but with my experience i would choose RHCS over RAC (when i would not need the performance of a RAC cluster) anytime. It is a lot cheaper, very easy to manage and is very well supported by the Red Hat support team.

Respect to the RHCS team, you rock!…..It’s because of you i sleep with out fear every night !

Laters,
Finnzi

Howdy,

I have been in a dilemma, trying to choose a good backup solution for this project i am working on. Previously i was using BackupExec there but i am looking at alternatives right now.

Obviously one of the reasons is that BackupExec costs a arm and a leg. I decided to look at Bacula and found it to be VERY good. However i found a huge problem (not in the software, more in the management part) and that is that i might not be around to do the management of Bacula. That’s why i am also looking at Arkeia. Arkeia has a very neat web interface that anyone that has done a restore/backup could work his way through. All settings are fairly obvious after 10 minutes of browsing. Now i just have to wait for the official offer from the Arkeia sales department to see if it fits my budget.

Bacula however seems to be a bit more advanced, if i was looking for a backup software to use for my own personal project or in a environment of linux administrators i would choose it over many commercial solutions if i had a tight budget. It’s easy to administer for anyone that is used to CLI environments and the tape format used is well documented. I am sure i will use this piece of software sometime in the not-so-distant future.

Bah…i will let you know how much the Arkeia sales department quotes me for the Net Backup software.

Laters,
Finnzi

Howdy,

My summer vacation started last monday and i went to Neskaupstadur (My birthplace) with my son on tuesday. So far it has been pretty good, i am redesigning the server environment for my fathers company, moving it to a fully virtualized environment and hoping to get recovery time in a total server failure down to 15-30 minutes….pretty good for a 25 man shop ….virtual machines rule!

On tuesday i bought a iPod nano and did some video converting of some very legal TV shows i legally downloaded from the “internets” so i could watch them on the extremly small screen of the iPod…it is good enought for the 55 minute flight from Reykjavik to Egilsstadir.

Tomorrow the IBM x3500 server arrives and i can start the installation & configuration of the new server. Hopefully no issues arrise. In the whole redesign i am planning on to replace the current commercial backup software with Bacula, a open-source project that seems to do everything i would need to do for a sweet backup…it even seems to be able to do tiered storage! ….this software rocks!

The mail server is currently running debian testing (yeah yeah, i know….i should not be running debian, or even debian testing for that matter in a production enviroment, i am a hardcore Red Hat person!) and will be replaced with a nice CentOS 5 virtual machine…

Then there are two Windows 2003 servers, one domain controller which acts as a print & file server also, and another server that runs some misc software.

Well….i am getting pretty damn tired here …Laters!
Finnzi