First impression on CentOS 7

After testing the new CentOS 7.0 here are my first impressions:centos7

  1. systemctl took some time to get into (learning done on my SuSE laptop distro)
  2. I  don’t really like the new FW config although I see some advantage there, if you already know iptables good enough not much to gain.
  3. The default CentOS 7 installer is very good, kickstart also works as a charm.
  4. I would love to see a kernel 3.13.xxx instead of the 3.10.xxx though (need to read what has been back-ported).
  5. The new default XFS file-system on CentOS 7 surprised me, and for the standard VMs install I’ve come back to ext4 with some custom options, you need to take attention to this specially if you are deploying small VMs. Big filesystems with more than 2 cores will benefit of using it.
  6. The network CentOS 7 configuration manager also changed and it’s better, nice to be able to fully use network-manager (nm), also the command line interface is really nice (nmtui).
  7. The boot loader is now grub2 instead of grub
  8. Also great the EPEL repo for CentOS 7 with all the goodies we are used to, you may install it just by running:

 

rpm -Uvh http://dl.fedoraproject.org/pub/epel/beta/7/x86_64/epel-release-7-0.2.noarch.rpm

 

I still think Redhat and it’s army of clones is ahead of all the major distribution to carry mission critical and deliver the best performance out of your boxes.

Great work CentOS team, and thank you Redhat!

PS – I’m also proud of Redhat 6, a few years ago I’ve installed an email cluster consisting of 2 servers and SAN storage this email cluster served 3000+ IMAP accounts(10GB quota, maildir format), the nice thing is since it was installed with Redhat 6.0 (one month after release aprox.) and it’s still running without reboots (4 years). This is impressive but now I hope my ex-work make update it to Redhat 7, although Redhat 6 support will still be available for until 2020.

TOR 0.4.17 for Redhat and it’s clones (CentOS, Scientific Linux, etc)

Hi!

Here is the new version of TOR rpm package, you may also install other mainstreams versions from EPEL, currently this one is the latest.

This package is for RHEL 6.4 and all it’s clones (CentOS, Scientific Linux, etc)

tor-0.2.4.17.rc-tor.0.rh6_4.x86_64

md5sum: 11bf2bf0e0185f85e9433d5c1b5ddeb8

scr code: https://www.torproject.org/dist/tor-0.2.4.17-rc.tar.gz

to install:

rpm -Uvh tor-0.2.4.17.rc-tor.0.rh6_4.x86_64

 

or

yum localinstall  tor-0.2.4.17.rc-tor.0.rh6_4.x86_64

 

Hope it helps,

Pedro Oliveira

Average file size on directory using gawk

gawk gnu awk

 

While tuning and benchmarking an HP backup device (HPD2D backup system) I needed to estimate the average file size of the IMAP server storage.
You may think I could just count the number of files and the divide the used space by the number of files, but that wasn’t the case because I didn’t want all the files to count, in this case I just needed the maildir files that have the email content.
So I did a little script (just a command line) using gawk to do it for me:

find /home/vmail -type f -name [0-9]* -exec ls -l {} \; | gawk '{sum += $5; n++;} END {print sum/n;}'

First I find all the files that starts with a number on the base directory of my dovecot server (IMAP storage), and the I need to list them as the size info is needed.
Second I’ve a little gawk script that will do the sum and division.
Let me say this took a few hours as the storage holding the files has 8TB of data.
Well hope this will help some1 else.
Cheers,
Pedro