CentOS 7 released on x86_64 (opens in new tab)

I installed it on VirtualBox (using a Windows host pc). I must say, my first impressions are that this is a very nice release.

They implemented the same new installer from Fedora, which I really like. It makes for 2 clicks (Language and Keyboard) and then it's installing in the background while you can setup your passwords and accounts. This makes for a very fast install.

The system just seems to feel "faster". I know that is completely objective, but mind you, I did not have the VirtualBox Guest Tools installed on the VM, and it still felt "native". I'm not sure what about it specifically feels faster, just everything I guess... especially booting.

eth0 was set to "ONBOOT=no" by default, which tripped me up for a half second (since all previous releases came with all adapters up). A quick config change and restart the network service, and up and running. I was surprised there was already update packages available, including a kernel update.

VirtualBox did not want to install it's Guest Additions/Tools on the VM, due to some change with "numa", from my understanding it's memory allocation related (could be wrong). In any event, I got the "struct mm_struct has no member named numa_next_reset" error.

Some digging around and I located this patch: https://www.virtualbox.org/ticket/12638

Applied it to the VirtualBox src once it unpacked itself to the /opt directory. After the patch, the Virtualbox Tools compile ok and installed.

I have a lot more playing around to do this evening... but so far, happy to say, this is shaping up to be a great release.

  [Unit]
  Description=The Apache HTTP Server
  After=remote-fs.target nss-lookup.target
  [Service]
  Type=notify
  EnvironmentFile=/etc/sysconfig/httpd
  ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND
  ExecReload=/usr/sbin/httpd $OPTIONS -k graceful
  ExecStop=/usr/sbin/httpd $OPTIONS -k graceful-stop
  KillSignal=SIGCONT
  PrivateTmp=true
  [Install]
  WantedBy=multi-user.target

I wouldn't expect to go to Windows' list of services, right click one and run arbitrary commands either.

    # /etc/init.d/mysqld configtest
    Usage: /etc/init.d/mysqld {start|stop|status|restart|condrestart|try-restart|reload|force-reload}

    # /etc/init.d/mysqld graceful
    Usage: /etc/init.d/mysqld {start|stop|status|restart|condrestart|try-restart|reload|force-reload}

What's 'graceful'? A particular signal?

This is what many people view un-unix like, a big dependency, that can't be replaced in the chain. The systemd developers also develop udev (which actually builds out of the same source tree as systemd), and there have been a few arguments about whether certain responsibilities are that of the kernel, or udev/userspace http://lwn.net/Articles/518942/, http://lwn.net/Articles/593676/. Systemd also touts its cgroup usage, though they view that they should be the only user of cgroups, since they are in a spot to "manage things properly" (which is partially true). (Some services have also started relying on systemd's cgroups to clean up orphan processes, which is bad for other init systems that don't do this).

So no one really hates how systemd works, just how its managed, and what it aims to do. If it were a simple init system and service manager, there would probably have been no arguments.

2) MAH FREEDOMS!

There are technical reasons people don't like systemd that are valid, but usually the die hard anti-systemd people boil down to hating Lennart Poettering and complaining about how the US Constitution must some where say they never have to use systemd.

There are some valid concerns (big scope, bloat, feature creep, etc) but they really haven't come to fruition, although are still valid concerns.

At the end of the day, without much effort or trouble of switching to systemd from OpenRC, my system boots faster, which is great.

systemd's declarative unit file syntax is easier to reason with, but comes at the expense of having to memorize a ton of options and being fundamentally dependent on the toolbox provided to you by systemd, since you can't code your way out of unconventional corner cases as easily.

The unit file syntax isn't the reason people complain, though.

http://wiki.centos.org/AdditionalResources/Repositories/SCL

I can see a bootstrapped company using CentOS, or a company running on angel/seed money. Once a company gets Series A funding though, you have to start wondering why they wouldn't upgrade to Red Hat. The message from the company basically is they'd prefer the sysadmin to spend their nights and weekends figuring out problems, instead of making a small payment for support service. This is the type of position you want to run, not walk from.

On a job interview, a good question for a sysadmin to ask an interviewer when they say "do you have any questions to ask me?", is, "Will I support any machines, operating systems or applications that are not under a vendor support contract?" Inevitably there will be one or two legacy machines or applications, but if you get a laundry list in response, run.