Just spent the better portion of my day fixing a buggered PHP installation…

The magic line:
–with-mysql –enable-shmop –enable-track-vars –enable-sockets –enable-sysvsem –enable-sysvshm –enable-magic-quotes –enable-mbstring –with-curl –with-mcrypt –with-freetype-dir=/usr –with-exec-dir=/usr/bin –with-mhash=shared –with-pear=/usr/share/pear –with-zlib –with-openssl –with-xml –enable-gd-native-ttf –with-png –with-zlib –with-zlib-dir=/usr –with-jpeg-dir=/usr –with-png-dir=/usr –with-gd=/usr

^^ MAKE SURE –with-gd=/usr is at THE END

Was playing around with using the loopback devices to mount some OS images on CentOS and following the losetup followed by a mount command would indeed mount the image, but umount wouldn’t unmount it and would leave it stagnant, leaving me with this error:

ioctl: LOOP_CLR_FD: Device or resource busy

Interestingly enough though the lomount command

lomount -diskimage OS.img -partition 1  /MOUNTFOLDER

and then using umount to unmount the mountfolder would unmount the loopback device properly and free it for re-use.

Hope this helps someone!

I’m always trying to find a good method of monitoring system performance and logging it, but today I ran into a rather strange issue that I couldn’t find on google.

sar 0 was returning high idle percentages:

# sar -u 0

08:17:29 AM       CPU     %user     %nice   %system   %iowait     %idle

08:17:29 AM       all     18.11      0.01     11.66     70.22    3549.42
running top didn't produce 3.5k % idle and in fact the system was nearly 98% idle. 
The quick fix is to simply run

yum update sysstat
That fixed the problem immediately on the box I was using.

Hope this helps someone else.