mount error (13): Permission denied

Running into cryptic errors really sucks, and this was certainly no exception. We had a Windows share provided to us that we wanted to mount to an Ubuntu 10.04 LTS server for general storage.

After reading the Ubuntu MountWindowsSharesPermanently wiki page and consulting the smbmount man page I came up with this new (initial) /etc/fstab entry:

//192.168.1.5/test-smb1 /mnt/it_hosted cifs credentials=/root/it_hosted_windows_share_mount.conf,iocharset=utf8,sec=ntlm2 0 0

The /root/it_hosted_windows_share_mount.conf file contained:

username=storageuser
password=SuperSecret
domain=example

I’ve substituted values of course. One thing to note is that if example.com were the real domain, I’ve made sure to use example as the value.

Then came the mount error (13): Permission denied error. I tried from a Windows box and was able to connect fine, so I knew that the server/share wasn’t the problem.

I then decided to call mount directly as shown here. After getting that working, I rechecked the syntax used in /etc/fstab and then finally looked at /root/it_hosted_windows_share_mount.conf again.

What do you know, the old & much despised EOL issue. After changing the DOS EOL to UNIX everything worked. I can’t count the number of times I’ve been bitten by that.

EMC VNXe 3100 Power Button

Just in case you also get caught by this, this particular storage array does not have a power button. Instead, once power is cycled (unplug the cords and replug), it will boot up and run internal diagnostics prior to powering back up. It took about 15-20 minutes for it come online again after it was safely shutdown.

If you have other hosts/services that depend on it to be online first, it is probably a good idea to wait for the array to come online first before powering them on, otherwise you’ll have to restart any services that depend on it.

SQL in easy steps, 3rd Edition errata

I was reading through SQL in easy steps, 3rd Edition and made it to page 152 where it covered Sub-query calculated fields. It’s a fancy way of saying a SELECT statement within a SELECT statement, but isn’t that hard to grasp if you’re familiar with how variable interpolation works with Bash or similar shells.

My problem was understanding how even though a column wasn’t listed as one to be returned by SELECT it was seemingly returned as a byproduct of an ORDER BY statement. I couldn’t find this mentioned in any of the MySQL documentation or another MySQL book I have so I was getting pretty frustrated. I fired my MySQL this morning and opened up subquery-calc.sql and had a good laugh: The mental block I was having was due to an error in the book’s code that wasn’t present in the SQL file.

I fired off an errata report in the hopes that it will be correct in future printings so others won’t be as confused as I was.

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