I always forget about my blogs
Posted on: Thursday, November 6, 2008 at 13:18:51
I've got work to do and I remembered about this. In short,
school is keeping me way busy. Everything on VPSLink, and on my
own VPS server is running well. I have a host set up on it at http://benderbrau.ath.cx that hosts
the robotics development server as well as my software engineering
project. I have some git repositories you can chek out if you want at
/git. Should I post my physics lab? I'm fairly proud
of them, but I fear that people will abuse it by plagarizing it. I
need to dig out some of my high school assignments, aah the memories.
VPSLink
Posted on: Sunday, July 6, 2008 at 13:18:51
Undertow has had
horrible uptime recently, with all the storms and everything. If there
wasn't a power outage, there was a network outage. I finally got sick
of it enough to find a different solution. I bought a virtual private
server (VPS) over at VPSLink. I
chose the cheapest option. It has 64MB of RAM, 2GB of drive space,
and 100GB bandwidth for the month. Its very minimal, but I'm enjoying
it so far. I have irssi running in screen along with bitlbee, and
I'm running lighttpd with php fcgi.
Memory doesn't seem to be a problem so far. Right now I am using less
than half of my allotted RAM. One really annoying issue about it is
that it can sometimes have really high latency, it gets annoying
really fast when you are in an ssh session on IRC, and writing a
blog post. One of the deciding factors in choosing VPSLink was that
it had a template image of my favorite operating system, Arch Linux.
My current RAM usage:
$free -m
total used free shared buffers cached
Mem: 62 26 35 0 0 0
-/+ buffers/cache: 26 35
Swap: 0 0 0
Uninterruptible Sleep
Posted on: Friday, May 23, 2008 at 13:18:50
So I compiled an OpenVZ
2.6.24-ovz004.1 with Arch's
kernel
patchset merged in. Everything seemed to work until I wanted to
shut down my test VE.
I found out the shutdown command was stuck in
state D (uninterruptible sleep). I did some more debugging, and noticed
that my rtorrent process suffered the same fate. I googled, debugged,
googled, debugged for a while, and noticed that the shutdown command was
stuck in the sync() system call. It seems that any process that calls
sync() would fall into state D. I figured it was a problem with the
merge, with the squashfs and aufs patches that Arch introduces.
Recompiling the kernel without the squashfs, and aufs patches seems to
work. I will give it some more time to see if it hangs again. I am also
running ovz005 from OpenVZ's git tree, though the bug reports, forums,
wiki, mailing list, revision logs, etc don't seem to say much about the
problem.
I'll package up my kernel, container initscripts and filesystem, and
upload it to the AUR when I've perfected it enough.
OpenVZ Server Isolation
Posted on: Wednesday, May 21, 2008 at 13:18:50
I spent all day yesterday trying to get Xen to compile and install on my
test server (aka my desktop). One thing after another wouldn't work. Xen
seems to have its own way of doing things which break compatibility with
the rest of the kernel. Finally I got tired of wresting with Xen, so I
researched for some more solutions. I found what I wanted, OpenVZ.
OpenVZ, like Xen is a vps solution for Linux. Unlike Xen, OpenVZ is
closer to a glorified chroot, rather than a glorified emulator. The
kernel is shared between all virtual environments (VE) on the host
machine. Processes on the host and processes on the VE are kept separate
but equal. Separate, where processes between VEs are unaware of each
other's existance, but equal in that they are the same process that
would run on an unmodified kernel.
I started looking into virtualization because I wanted to let others use
my machine for development, and IRCing purposes, but I didn't want to
let them in on my private space. (I make sure my permissions are set
correctly and whatnot, but I'm paranoid). I sometimes need to evaluate
server packages, but I want to lower the risk of an exploit due to
misconfiguration.
I originally started working with qemu/kqemu, but I found that too slow
to be effective on my Athlon XP 2000+ with 768Mb RAM. So I started
looking into Xen, and that didn't work out. Now I am here working with
OpenVZ.
I started off downloading the
OpenVZ packages off of the Arch
Linux User Repository and I merged the OpenVZ patchset with the
stock -ARCH patchset, and tweaking the PKGBUILD. Eventually I got it to
compile. Then I compiled the nvidia driver for the new kernel, and I
built the OpenVZ utilities. I will upload these files soon, and I will
send the original contributor my changes when I am satisfied with them.
Now I am working on templating an ArchLinux OpenVZ container. Once this
is done, I will have a base install to work off of (Just like bare metal
Arch :). I can host this somewhere better than this site so others can
benifit from my work.
Once this is done I can create a robotics VPS with toolchains for
everyone to develop on. As well as a site to host pictures. Expect
robotics.penguinflavored.com sometime.
Forward Emails To Your Cell Phone Using GMail
Posted on: Tuesday, January 15, 2008 at 13:18:51
Do you wish for others to contact you by SMS without giving them your
phone number? Are you a systems administator who needs to be notified
quickly if a server goes down? Would you like to receive emails by SMS?
If so, you probably want to forward emails to your cell phone using
your provider's smail to SMS gateway.
Many providers offer cell phone owners an email address that converts
email to SMS which sends directly to your phone. The
Wikipedia has a
list of providers who offer email to SMS gateways. The local
part of the adress is usually your 10-digit phone number such as
1234567890. You can send a test email to this address to see if you
receive an SMS on your phone.
Now, you don't want to remember this unmemorable address, and you
certainly don't want others to have to remember it. You may even
want to keep your phone number private, but allow people to text
message you. In this case you can have email forwarded from another
account. If you are a GMail user you can take advantage of GMail's
plus addressing and filters.
With plus addressing any email sent to john.doe@gmail.com,
john.doe+mobile@gmail.com, john.doe+anything@gmail.com. Will be
delivered to john.doe's account.
Other sites mention the spam fighting uses for this feature. But
we are going to use this to direct special emails to our cell phones.
- Create a new filter under Settings->Filters.
- Under the 'To:' field, enter the address you want forwarded to
your phone. For example john.doe+cell@gmail.com.
- Go to the Next Step.
- Enter your cell phone's SMS email address.
- Finish by clicking 'Create Filter'.
- Test it by sending an email to this address (You won't be able
to send it from your GMail account (that will cause infinate loops), so
you'll have to send it from another email account, or have a friend send
it).
Depending on how private your line is you may want to restrict the
number to certain senders. You can do this by adding a secret string
after the + that you only give to a few people, or by filtering on
the From: header.
