Oracle Musings

Almost exactly one year ago, I wrote about the lack of hosted Oracle database packages.  Since then I haven’t seen much movement on that front, until last week, when STRATO AG, a German hosting company started offering a STRATO Oracle Server hosting package based on Parallels Virtuozzo Containers and Oracle Express Edition.  Here’s the press release.  I’m having a bit of trouble finding the package on the STRATO site, but if it’s true it’s another valuable option out there for ways to increase Oracle usage at the low end (where a lot of innovation takes place).  I’m curious how STRATO is handling the Oracle licensing issues…

So I’ve been working to push out OEM Agents from our Grid Control OMS on Windows XP to a couple of Linux servers running OEL 5.  It’s been a lot of fun, and I thought I’d share of the obstacles I overcame:

1. SSH User Equivalence. 

You need to get this working before anything else will work.  Fortunately there’s a pretty good script in oracle/oms10g/sysman/prov/resources/scripts that will do the hard work for you.  However, my first run of this resulted in (BTW, this is all run from a Cygwin bash shell since all of the scripts are Unix-based):

./sshUserSetupNT.sh.org: line 17: $’\r’: command not found
./sshUserSetupNT.sh.org: line 20: $’\r’: command not found
./sshUserSetupNT.sh.org: line 27: $’\r’: command not found
./sshUserSetupNT.sh.org: line 231: syntax error near unexpected token `elif’
./sshUserSetupNT.sh.org: line 231: `   elif ! test -f “$CLUSTER_CONFIGURATION_FI’E”

Couldn’t find much info in Metalink on this — turns out I needed to dos2unix the file before running it.

Also, the documentation on running this script is pretty good — especially this section.

2. You have to be careful with your Cygwin installation — I usually have Cygwin running anyway, and I install the net tools like telnet, ssh, ping, etc. 

However, I got errors saying that the following command in the .sh script was failing:

ping $host -n 5 -w 5

With the following message:

Usage:  ping [-dfqrv] host [packetsize [count [preload]]]

Turns out the Cygwin ping command doesn’t implement the -n and -w options.

Solution was to replace the ping command in the script with /cygdrive/c/windows/system32/ping.exe

3. Also turns out I didn’t actually have a Linux agent staged, even though I had a /oms10g/sysman/agent_download/10.2.0.2.0/linux directory, I didn’t have an oui/oui_linux.jar file.  Once I downloaded that and unzipped it cleanly, I still got some odd errors.

Searching Metalink, you’ll see some references to an oddly named file: OC4J~OC4J_EMPROV~default_island~1.  It’s a log file kept in /oms10g/opmn/logs and it has a lot of detail about the attempt to deploy the agent.  I was getting the following error:

error:  cannot open zipfile [ /app/oracle/product/agent/tmp/oui/oui_linux.jar ]
unzip:  cannot find /app/oracle/product/agent/tmp/oui/oui_linux.jar, /app/oracle/product/agent/tmp/oui/oui_linux.jar.zip or /app/oracle/product/agent/tmp/oui/oui_linux.jar.ZIP.
chmod: cannot access `/app/oracle/product/agent/tmp/oui/Disk1/’: No such file or directory
chmod: cannot access `/app/oracle/product/agent/tmp/oui/Disk1/install/unzip’: No such file or directory

This even though I had the oui_linux.jar file and it clearly transferred to the target machine, I could see it:

$ ls -l
total 42884
———-+ 1 oracle oinstall 43909460 May  5  2006 oui_linux.jar

Odd, why are the permissions 000 instead of 755?

Turns out the permissions on the Windows side were 000 and the script uses scp -p to transfer the file (and retain permissions), so the unjar command on the remote host couldn’t see the file.  I didn’t know you could create a file with 000 permissions on it, although I guess it makes sense — you’d have to chmod it to 000 after creating it though.  A quick chmod command on the Windows side fixed this.

4. Finally I ran into something I haven’t solved yet — I’m running OEL 5 (redhat-5) and the Installer doesn’t recognize that as a supported O/S (it’s looking for redhat-3 and redhat-4).  I’m trying different ways around that but haven’t quite gotten it.

No, I’m not describing anyone’s personality, least of all my own

I should title this series “An Oracle person’s experiences as a Linux SA”….

From my earlier posting, you all know that I like xterms with dark backgrounds and white foregrounds.  I’ve always liked typing that way — probably from my old terminal days.  I gave up on trying to make MS Word (You can do white on blue, albeit it’s a very bright blue) do that — and anyway word processing is different than a terminal to me any day.

Of course, Linux likes to colorize directory listings — and I can’t see the dark, dark blue of directory entries against my black background.  So, on to figuring out why it’s doing that and to make it stop…

LS_OPTIONS looks like it will do the trick, so I set it to –color=none and export it into my environment.  No luck.  Maybe it needs to be set in my login shell, and since it’s my machine and I think everyone should turn it off, I edit /etc/profile and set it there.  Logout / login — still no luck.

Maybe ls is aliased?  Yep — I run “alias ls” and I see that it is.  Since I don’t have an alias file I wonder where global aliases are set.  Maybe /etc/alias or /etc/aliases?  No, no such file exists.

Go back and look at /etc/profile — at the end of the file it goes to /etc/profile.d and runs every .sh file in that directory — odd.  One of those is colorls.sh which of course sets a whole bunch of aliases for ls.  So I rename colorls.sh to colorls.sh.org, re-login and poof!  No more colors.

I don’t like aliasing commands — leads  to confusion.  About the only commands I alias are cd and vi (points to vim nowadays….).

Edit: I’ve since learned that LS_OPTIONS doesn’t do anything anyway — ls doesn’t look at it.  It’s only used when aliasing ls… (rolls eyes).

Ok, now on to the cool stuff.  From my earlier post, you may be aware that I have a machine grant (or, to put it another way, domain0) — with 2 Xen VMs (sherman and mcpherson).  Actually, sherman and mcpherson are more like placeholders for VMs — I want to be able to test out different configurations in each one, re-using the same IP address.  So I’ve actually got sherman01 and mcpherson01.  Today I wondered how hard it would be to create sherman02 or simply clone sherman01.  It turned out to be dead simple:

1. Go to /etc/xen and copy the sherman01 config file to sherman02
2. Edit the sherman02 config file replacing all references to sherman01 with sherman02
3. Since I’m using file-backed VMs, copy the files representing the disks for sherman01 to sherman02 equivalents and make sure the config file references them
4. Shutdown sherman01
5. Start sherman02

Worked like a charm.

Ok, I added some space to one Xen VM this morning.  Wasn’t too bad, although there are so many ways to do this in Linux.  I wanted to do something simple.  Create a file on the host O/S (grant), attach it to the VM (sherman) and then just add it into the filesystem.  I was surprised at the number of commands I had to run, but they all made sense:

1. Use dd to create a file on grant that will become a new disk on sherman
2. Shutdown sherman using xm shutdown
3. Edit the sherman configuration file under /etc/xen to add the new file as another disk (took me a minute to remember the disk naming conventions)
4. Re-start (”re-create”) sherman so that it recognizes the disk
5. Use fdisk to partition the disk on sherman using a primary partition and changing the type to 8e so that the Linux LVM can manage it (Look at all the types!)
6. Use pvcreate to create a new physical volume on the device partition
7. Use vgscan to look at the volume groups
8. Use vgdisplay to display the current volume group
9. Use vgextend to add the new physical volume to the volume group
10. Use lvscan to verify the addition
11. Use lvextend to extend the logical volume onto the newly added space
12. Use resize2fs to extend the filesystem to the newly extended logical volume space

Whew!

Many thanks to the following:

1. Re: Adding more space to the system without using LVM in the host
2. Extend Your MythDora Video Partition using LVM
3. Extending a logical volume