Archive for November, 2009

Debugging broken mail daemons

Monday, November 30th, 2009 by Liz Quilty

Getting bounced mail? here let me try and explain a few of the more common problems.

Have you added the domain to accept mail?

You need to add the domain into the mail server so it knows to accept email for it. If it accepts mail for every domain then its fairly easy for somebody to attack your server and fill up your hard drives. There is no one solution for this one at all because of the multitude of server setups and configurations.

For the basic Rimuhosting setup you can just edit /etc/postfix/main.cf and look for the line

mydestination = $myhostname, localhost.$mydomain, localhost

Add in any domains you want into here, usually it will have something like the above which should be left , just add a comma and append the new domain name.

If you are using virtual users then this will be virtual_mailbox_domains line possibly unless you are using a file.

Does the user exist?

Check that the user in the username@domain.com actually exists. Did you add the user? check also that its all lower case at both ends, whilst english tends to make us want to use upper case, its generally a bad idea. Linux is case sensitive and this can cause problems.

Restarted mail server

So you added the user, checked the domain is in there, all configs checked and working, but did you restart the mail daemon? this can be usually done with

/etc/init.d/postfix restart

Check DNS?

Check your MX record exists and points to a domain name. Then check that domain name points to your VPS IP address. An MX record can’t point to just an IP address, some people add mail.domain.com and point that to the IP address which keeps things tidy.

Another thing to check, if you host your mail on gmail, and are having sending mail to your domain name from your VPS, often Plesk or Virtualmin or similar has added the domain to local DNS. This means it thinks that this machine hosts mail for you when in fact it may be elsewhere. The easy fix for this is to remove the DNS server for localhost. edit /etc/resolv.conf and remove or comment out the following line

nameserver 127.0.0.1

Careful when upgrading

Often we have had emails that just suddenly ‘stop working’ and people have not upgraded or updated in a while, what they may have done is upgraded packages which overwrote configs. It pays to backup your working configs often, and check what packages are being upgraded.

If for any reason you get stuck and things break, just drop in a ticket for us to take a look and fix things.

Karmic Koala VPS Images Available

Thursday, November 26th, 2009 by davidmace

The latest 6 monthly Ubuntu build, Karmic Koala, was released to the public on Oct, 29th.  That is now an option when ordering a new VPS  or for a fresh install on an existing VPS (contact us if you have questions about retaining your data after the reinstall).

If you don’t want to reinstall an existing server, but you would still like to use the latest release, a simple apt-get dist-upgrade can bring you from Jaunty Jackalope (9.04) directly to Karmic.  I’m only aware of 1 issue that has cropped up which, as Liz noted, can be remedied with a simple kernel change.

Ubuntu’s 6 monthly build schedule offers a support window of 18 months via the standard Ubuntu repositories.  The scheduled end-of-life for Karmic is April, 2011.  LTS releases (next one scheduled for April, 2010) bring about longer support windows (5yr for server releases) and I prefer those for production systems.  Although given the relative easy of distro upgrades with Debian derivatives, this isn’t a major sticking point with me since it’s usually pretty painless to move forward 1 release at a time via dist-upgrades.  All end-of-life dates can be found on the Ubuntu wiki.

Karmic brings along bug fixes and minor package updates, but I’m not aware of any major changes or package upgrades.  If you would like to see what versions of your required software have been packages in the main repositories, you can view those at distrowatch.org.

If you need any help planning a migration to the new release or if you just have some questions about Ubuntu in general contact our support team and we will help.

32bit or 64bit – Choose Your VPS Kernel

Thursday, November 26th, 2009 by davidmace

Sometimes we roll out new features in our control panel without announcing them.  We usually do this so that we see a trickle of new users initially which helps identify any bugs or missing functionality before the entire userbase starts hammering the new features.  :)

Selecting your VPS kernel bit-edness (32bit or 64bit) is one feature that’s been available for a wee bit, but we haven’t made an effort to spread the word on that.  You can find this option inside your normal control panel in the ‘vps info’ box.  Or you could go there directlly here.

You’ll find a list of the kernels available to you with some comments by our kernel maintainer alongside most of those.  If you’re on a 32bit distro (most users fall into this category), it’s fine to enable a 64bit kernel; you’re not going to break your setup.  But before you go running out and switching over to the 64bit version of your favorite kernel, make sure that you really need all that bit-ed goodness.

Your memory usage is going to go up once you switch over to a 64bit kernel.  A lot of that has to do with integer size and memory pointers, both of which are now twice the size.  You’re not going to see a doubling of the memory required, but you will see a bit of a jump.  If you’re already running tight on RAM, you may need to increase your RAM after you changeover.

What about server performance?  Will that be any faster?  Most likely no.  All of the speed comparisons I’ve seen show only slight performance differences between them.  Those test sometimes favored the 32bit version and sometimes the 64bit version – far from conclusive evidence.

Well if there isn’t much of a difference, why are we having this conversation then?  Per-process memory availability is a big one.  With 32bit kernels, you’re limited in the amount of RAM that a single process can access.  That limit is 2GB which is plenty for most VPS users, but if you’re running large memcached daemons or just want to have a huge jvm stack allocated to Tomcat then you may want to consider going to a 64bit kernel.

In additional to your choice of kernels, we do offer native 64bit distros for a fresh install.  You can do this from your control panel if you’d like to replace your entire VPS with a fresh image with the associated 64bit libraries.

Pacman Cookies at Rimuhosting.com

Thursday, November 26th, 2009 by Liz Quilty

Last night i spent a while making Pacman cookies, i brought them into the office today.

The idea originated from when i was making Xmas Mince pies, i cut the circle then cut a V out so i wouldn’t have leftover dough. Since i was doing a cookie swap at the time i made a quick mock up with the Pie Dough which my kids loved.

I gathered my cookie mixture together in the following few days, and did some research (clearly not enough, i almost only made 3 Ghosts when there are 4!), then sat down one night to make the cookies.

I took photos of the process for you to have a giggle. Apologies for the poor photo quality, It was night from 9pm-1am , i don’t have a decent flash unit etc. I made 3 sets, one for each of the people in the cookie swap, and one as a spare in case things went wrong which i took to work.

After wiping the conference room table, i placed the cookies out in a pattern, everyone loved it and wanted to eat it,. John grabbed a Ghost immediately, and then there was talk about ‘you cant eat the ghost until you get a powerup! and you need Pacman to eat his way along the line to get to those!.

So for the rest of the day everyone would eat a small cookie, and move Pacman along a pace whilst making the ‘waga waga’ noise. Slowly they all disappeared.

You can find the full photo set here http://www.flickr.com/photos/wishes/sets/72157622749111189/

Pacman Cookies Pacman Cookies Pacman Cookies Pacman Cookies Pacman Cookies

Pacman Cookies Pacman Cookies Pacman Cookies Pacman Cookies Pacman Cookies

apache modules to help keep your system steady

Monday, November 23rd, 2009 by Liz Quilty

libapache2-mod-bw – bandwidth limiting module

This module allows you to limit bandwidth usage on every virtual host or directory or to restrict the number of simultaneous connections.

The bandwidth control, for example, can be configured according to the criteria: origin of the connection, file extension, file size or user agent of the client.
Example:

LoadModule bw_module /usr/lib/apache2/modules/mod_bw.so
BandWidthModule On
BandWidth all 40000
MinBandWidth all 10000
ForceBandWidthModule On

libapache2-mod-defensible – module for Apache2 which provides DNSBL usage

mod_defensible implements usage of DNSBL servers to block access to a Web site or to specific locations.

Example:

DnsblUse On
DnsblServers httpbl.abuse.ch sbl-xbl.spamhaus.org
DnsblNameserver 145.253.2.75

libapache2-mod-evasive – evasive module to minimize HTTP DoS or brute force attacks

mod_evasive is an evasive maneuvers module for Apache to provide some protection in the event of an HTTP DoS or DDoS attack or brute force attack.

It is also designed to be a detection tool, and can be easily configured to talk to ipchains, firewalls, routers, and etcetera.

Example:

<IfModule mod_evasive20.c>
DOSHashTableSize 3097
DOSPageCount 5
DOSSiteCount 100
DOSPageInterval 1
DOSSiteInterval 1
DOSBlockingPeriod 600
</IfModule>

Comes with a perl script to test it also.

vps:/etc/apache2/mods-available# perl /usr/share/doc/libapache2-mod-evasive/examples/test.pl
HTTP/1.1 200 OK
HTTP/1.1 200 OK
HTTP/1.1 200 OK
HTTP/1.1 200 OK
HTTP/1.1 200 OK
HTTP/1.1 200 OK
HTTP/1.1 403 Forbidden
HTTP/1.1 403 Forbidden
HTTP/1.1 403 Forbidden
HTTP/1.1 403 Forbidden

libapache2-mod-line-edit – search-and-replace line editor module for apache 2

mod_line_edit is a general-purpose apache 2 filter for text documents. It operates as a simple on-the-fly line editor, applying search-and-replace rules defined in a configuration or .htaccess file. Both simple text and regular expression search and replace are supported.

Example:

SetOutputFilter    line-editor
SetEnv    LineEdit “text/plain;text/css;text/html”
LELineEnd ANY
LERewriteRule https?://(www\.)?example\.com http://example-development.yoursite.co.nz Ri

Throw something like that into your or somewhere and you instantly fixed all those problem URLS on your development system, without touching the source files at all.
This is ideal to stop/prevent people exploiting various holes in web applications and inserting javascript redirects etc.

Please note: the name of all these modules is debian/ubuntu related. Centos or RedHat based distros may have another name for the same modules. If you need any of these installed just drop an email into the support box and let us know.

Twitter Competition – Who won?

Friday, November 20th, 2009 by Liz Quilty

The randomly chosen main prize of $100 VPS Hosting credit went to a guy called Simon W  @simon_whttp://simon.geek.nz/

Simon had been desperate to get away from shared hosting. He couldn’t afford to move to his own VPS for another couple of months, so we really happy that he won.

We decided because we had so many great entries to do some runners up, and selected another 5 to get a $50 voucher. These were:
@dialogCRM
@stevenn
@GeekGirlCamp
@genevate – Who was already a customer and just got a credit
@pollyplummer

RimuHosting launches NZ-based VPS hosting

Friday, November 20th, 2009 by Peter Bryant

I am happy to announce RimuHosting is now offering NZ-based VPS hosting.

The plans are listed at http://rimuhosting.com/auckland-servers

RimuHosting is an NZ company.  But we have never hosted servers from NZ-before.  Most of our customers (and therefore servers) are over in the US and the UK.

So a couple of weeks back had our San Diego based server builder, RackmountsEtc ship us some Supermicro servers with dual Nehalems (2xE5506), 48GB of DDR3 ECC memory, and whopping 8TB worth of disk  (ridiculous!).

They duly arrived in customs the other day.  And then FedEx trucked them down at our Cambridge office on Wednesday.

It is a rare event for our Kiwi staff ever to actually see one of our physical servers.  Typically we buy machines and they are shipped direct to the data centers we use.  Where we prep them up remotely (via KVMoIPs, or PXE boot, or kickstarts).

While it was great to see the machines up close, the noise was horrific.  So we were glad when they were prepped up, mem tested, stressed and sent back up  to the well regarded Auckland-based Orcon data center.

The machines are now racked up, IPs assigned, and ready for VPS customers.  And we’re looking forward to setting up our first new customers on them.

WordPress Update Script – 2.8.6 and WordPress MU 2.8.5.2

Monday, November 16th, 2009 by Liz Quilty

New WordPress came out last Friday,  Sorry about the delay updating the script.

This script will update all instances of wordpress that are not the most current. Run it as root, it will make backups in /root/wp_upgrades of both databases and files in case things go wrong.

It will determine if its a WordPress or WordPress Multi User and apply the correct fix.

wget http://b.ri.mu/files/wordpress-upgrade-2.8.6.sh
sh wordpress-upgrade-2.8.6.sh

You may need to change the ownership of the wordpress files after install, I will fix this bug and write it into the script in the next couple of versions.

If you have any bugs or problems with it, please let me know or contact support

Twitter competition: Win $100 worth of RimuHosting hosting credits

Tuesday, November 10th, 2009 by Peter Bryant

For a bit of fun RimuHosting is giving away a $100 VPS hosting credit.  For example, that is 5 months’ worth of MiroVPS1 hosting  for your  own website!

To enter just re-tweet this message:

RT: @rimuhosting is giving away $100 worth of VPS hosting credits. Visit http://tinyurl.com/twittercredits for more info!

Click for an easy retweet

You can re-tweet the message up to a few times a day. Each of these tweets will be eligible and a winner chosen randomly by the guys (and one gal) at RimuHosting.

If the winner is an open source developer, let us know and we will double the credits to $200.

No bots or automated scripts please, this is meant to be a bit of fun!

We will direct message the winner so follow @rimuhosting to find out if you’ve won!

The competition is open now and we will do the draw before Friday, November 20, 2009.

The credits are transferable to anyone of your choosing, just let us know who they are at that time.  You can be an existing or a new customer.  Credits apply to VPS hosting only.

RimuHosting provides  Linux VPS hosting services.  You can read more about us here http://rimuhosting.com/support/aboutrh.jsp

See our VPS hosting plans.

RimuHosting takes over the operation of HostingDirect’s VPSs

Friday, November 6th, 2009 by Peter Bryant

Today RimuHosting has entered into an agreement to take over the operation of HostingDirect’s VPSs and their billing.

Ben Simpson of Hosting Direct emailed some of his VPS customers today saying:

Morgan from Hosting Direct will be leaving the team on the 12th of November 2009, he was the one who created the VPS infrastructure and supported it, Hosting Direct does not have the know-how to support or manage the VPS systems any-longer.

Ben approached me a few days ago to ask us if we could ‘take over’ their VPS servers.

I was keen for us to (finally) have a presence here in NZ.  Something a lot of our current customers have been ‘bugging’ us about for a while now.  So this seemed a great opportunity for us.

So while our deal is done, our work has just begun.  I don’t believe anyone can ‘buy’ customers.  Rather I consider we now have the opportunity to provide great service and ‘win’ our new customers.

I’ll be updating this post with any ‘frequently asked questions’ we get about the HostingDirect agreement.

Welcome to our network all the ex-HostingDirect VPS customers!

FAQs:

Q: Hosting direct doesn’t have data caps, has this changed with you guys

A: This has not changed with us.

Q: Will the date of billing cycles remain the same?

A: Most of our customers pay on the first of the month, so I was planning on re-aligning the dates to the first of the month after the end of your current billing cycle.  Making your first payment probably on the first of December.  We will be sending out an email about the billing next week.

Q: Will the price change?

A: We have no plans to increase ex-HostingDirect customers’ monthly fees.