macdiggs.com

Yes, you can do it very easy and fast if you have Webmin installed on your server.

Go to Servers -> Sendmail Configuration -> Sendmail Options and make sure that SMTP port options parameters are set to:

Name=MTA
Port=587, Name=MSA, M=E

Just like on the screenshot below:

Click "Save and Apply" button and you're done. Now your mail server will accept mail on both 25 and 587 ports.

I have migrated all my Ruby on Rails system from Fedora Core 6 to RedHat 4.5 recently, and everything was fine, except for that the feature of blogging by email was broken (got a phone call today about that).

I use standard sendmail/procmail integration feature to receive mail to a designated address,  and then pipe it into Rails Mailer's receive function.

So, it looks like that in my /etc/mail/virtusertable:

m@example.com        examplemobile

this way all email which is coming to m@example.com address will be forwarded to system user called examplemobile.

In order to process the mail further and pipe it into my Rails script, I have the following setup in my /etc/aliases file :

examplemobile: "|/usr/local/bin/ruby /var/www/html/examplesite/current/script/runner -e production 'Mailman.receive STDIN.read'"

This setup worked perfectly on Fedora, but broke under RedHat. What's the problem? I was getting the following errors in my maillog:

Feb 13 11:45:33 appserv1 sendmail[32000]: m1D2jXJw032000: from=<xxxxxx@c.vodafone.ne.jp>, size=397, class=0, nrcpts=1, msgid=<20080213114719020972.1b6f@0016E68C4270>, proto=SMTP, daemon=MTA, relay=mmrts035p01c.softbank.ne.jp [123.108.236.87]
Feb 13 11:45:33 appserv1 smrsh: uid 8: attempt to use "ruby /var/www/html/examplesite/current/script/runner -e production 'Mailman.receive STDIN.read'" (stat failed)
Feb 13 11:45:33 appserv1 sendmail[32001]: m1D2jXJw032000: to="|/usr/local/bin/ruby /var/www/html/examplesite/current/script/runner -e production 'Mailman.receive STDIN.read'", ctladdr=<m@examplesite.com> (8/0), delay=00:00:00, xdelay=00:00:00, mailer=prog, pri=30623, dsn=5.0.0, stat=Service unavailable

The problem turned out to be in sendmail setup under RedHat was more secure than the one I had in Fedora. Specifically, this has to do with smrsh (or Sendmail Restricted Shell) thingy. More info about it here. Basically, sendmail only allows piping to programs which (or aliases to them) are present in /etc/smrsh directory.

Since I only use ruby to pipe to, I have added a symbolic link to it inside the /etc/smrsh directory:

[mike@appserv1 smrsh]$ pwd
/etc/smrsh
[mike@appserv1 smrsh]$ ls -l
lrwxrwxrwx  1 root root 19 Feb 13 11:50 ruby -> /usr/local/bin/ruby

Everything works as it should now, and our mobile-blogging users are supposedly happy again :)

Though I have moved my latest Rails apps to Rails 2.0, I've been pretty slow moving my deployment recipes from older Capistrano 1.x to the new Capistrano 2.x series.

Capistrano ultimately lacks any documentation which can even remotely be called "complete" or "easy to understand", so it definitely takes much more time that it actually should take, to understand how the bloody thing works. Sure, this of course includes annoying trips into Cap's source code and stuff like that, which is not a great time saver.. End of rant.

Anyways, you can be a lazy folk like myself lately, and just deploy your Rails 2.x compatible app using old Capistrano 1.2 recipes:

cap _1.2.0_ deploy

But the time will come and you'll want to ultimately move the stuff to the latest and greatest. And actually, it's pretty easy to do, _once_ you got the idea what needs to be done.

First, you need to capify your application, using

capify .

command in the top level of your application.

Next, you can replace contents of your old deploy.rb file with the following (or modified the following).

set :application, "your_application"

set :repository, "https://your-repository.com/svn/#{application}/trunk"
set :deploy_to, "/var/www/html/#{application}"

set :mongrel_config, "#{current_path}/config/mongrel_cluster.yml"
set :runner, "mike" #the default user is 'app'
set :deploy_via, :export
set :deploy_via, :remote_cache

set :keep_releases, "3"

role :web, "appserv1"
role :app, "appserv1"
role :db,  "dbserv1", :primary => true

namespace :deploy do

desc "Create symlinks for shared image upload directories"
task :after_update_code do
%w{gallery_items attachments image}.each do |share|
run "rm -rf #{release_path}/public/#{share}"
run "mkdir -p #{shared_path}/system/#{share}"
run "ln -nfs #{shared_path}/system/#{share} #{release_path}/public/#{share}"
end
end

desc "Restarts the pack of mongrels"
task :restart, :roles => :app do
restart_mongrel_cluster
restart_apache
end

desc "Restarts apache web server"
task :restart_apache, :roles => :app do
sudo "/usr/sbin/apachectl graceful"
end

end

desc "Start the mongrels"
task :start_mongrel_cluster, :roles => :app do
sudo "mongrel_rails cluster::start -C #{mongrel_config}"
end

desc "Stop the mongrels"
task :stop_mongrel_cluster, :roles => :app do
sudo "mongrel_rails cluster::stop -C #{mongrel_config}"
end

desc "Restart the mongrels"
task :restart_mongrel_cluster, :roles => :app do
stop_mongrel_cluster
sudo "rm -rf #{current_path}/tmp/pids/mongrel.*.pid"
start_mongrel_cluster
end

This assumes you run your apps on mongrels cluster, and that you wish to restart your apache server after every deployment (somehow, just restarting mongrels just don't work for me sometimes). Also, I use different servers for application and database. Other than that, it should work for you as is.

But of course, don't really believe me, and look thru this config before messing up with your deployment stuff :)

I've been getting a strange "User unknown" error from sendmail today, when everything should have worked fine and even though users did exist. Here's some info on the problem's source and solution.

We have a domain called "talentnavi.biz", and I was asked to add a new subdomain to that domain ("kansai.talentnavi.biz"), and add new email addresses for several users who will be using that domain. I have setup everything properly on the server site by adding users and updating local domains and virtusers lists, however, when I was trying to test the delivery of the messages, I was getting "User unknown" errors and my emails to the newly-created mailboxes were bounced back.

I checked my mail server's logs, but there were of no help at all. After some googling, I found a very nice solution! In order to see how an email to a particular email address gets delivered, you should run the following command as root:

sendmail -d60.5 -d27.2 -bv info@example.com

So, in my case the command and output were as follows:

[root@me-ja mike]# sendmail -d60.5 -d27.2 -bv info@kansai.talentnavi.biz
map_lookup(dequote, mike, %0=mike) => NOT FOUND (0)
map_lookup(host, kansai.talentnavi.biz, %0=kansai.talentnavi.biz) => talentnavi.biz. (0)
map_lookup(dequote, info, %0=info) => NOT FOUND (0)
map_lookup(virtuser, info@talentnavi.biz, %0=info@talentnavi.biz, %1=info) => NOT FOUND (0)
map_lookup(virtuser, @talentnavi.biz, %0=@talentnavi.biz, %1=info) => NOT FOUND (0)
alias(info)
info@kansai.talentnavi.biz… User unknown

So, turns out that I have incorrectly configured my DNS records. They were set up like the following:

talentnavi.biz A 123.123.123.123

talentnavi.biz MX talentnavi.biz

kansai.talentnavi.biz CNAME talentnavi.biz

So, by default, the kansai.talentnavi.biz was aliased to talentnavi.biz, and since I didn't have a separate MX record for kansai.talentnavi.biz, the talentnavi.biz was used for mail delivery.

mike-meja:~ mike$ host -t mx kansai.talentnavi.biz
kansai.talentnavi.biz is an alias for talentnavi.biz.
talentnavi.biz mail is handled by 20 talentnavi.biz.

Therefore, the all email which was sent to "info@kansai.talentnavi.biz", was actually attempted to be delivered to "info@talentnavi.biz", because there was no separate MX record for the kansai. subdomain.

The solution is of course to add :

kansai.talentnavi.biz MX kansai.talentnavi.biz

Record to DNS server, and everything should work fine.

We have finally set up something which might be called a server room, at the company I work at.

We now have 4 servers, two of which are pretty powerful Dell PowerEdge 1900 servers I blogged about some time ago, one is our old server (which is basically just a custom-built stock computer), and one Mac which only serves a simple MySQL and FileMaker databases.

Now, my job for the next severals weeks is to gradually migrate stuff from old server to the new ones, which will become a PITA for sure, but I just hope it won't turn into MAJOR PITA :)

Just a quick follow-up to my yesterday's entry..

I spent the whole bloody day yesterday trying to make things work the way they should, and only got Seg faults on my application server as the result. Well, today I just re-installed everything I need from source, all the latest versions of the software - graphics & text processing libs, ImageMagic, Apache, PHP, Ruby and Rails of course with a slew of gems I use (including the latest rmagick, of course) - and now everything works together perfectly.

The whole process took me slightly less than 2 hours, and that includes reinstalling OS from the scratch, using Dell's installation disks! How about that huh?..

Talking about Dell-supplied install stuff… It is not bad, but come on - after default OS install is complete, you can not even remove packages you don't need without getting an error (" you need to install blah-blah-blah packages in order to remove bah-bah-bah packages " huh?!?)

Oh well. There's still that problem with gettext gem throwing errors in production mode which I solved somehow, long time ago - need to re-fix it and I'm ready to move everything from the old weaker server to the new powerful 2-server system.

I've been working on setting up two RedHat-based Dell servers at work today.  We have RedHat 4.5 on both machines, with RedHat subscription on one of them (the other one is for DB serving only with extremely limited access to it, so no need to spend money for updated software or patches)

The problem is that I needed to install and configure the environment for my Ruby on Rails based portal systems hosting. New servers, relatively new OS (there's no RHEL 5 for Japanese users yet :/ ), software subscription allowing to install stuff with a single mouse click (well.. literally, that is). What could possibly go wrong?

Well.. RHEL 4.5 went wrong. I just don't get it WHY the software which is piped to the server thru up2date program is so hopelessly, horribly outdated. Apache is at version 2.0.xx, PHP is stuck at 4.x, ImageMagick is at 3.0x, etc, etc…

And I need Apache 2.2 in order to use load balancing feature, RMagick for Rails doesn't want to work with ImageMagick < 3.6.x, PHP 4 just plain sucks (come on! We're at 5.2x series already! Not stable enough huh?). And of course everything gets installed by randomly spreading files over the disk (well.. that's how RHEL works, but I like to have everything/most stuff inside my precious /usr/local directory)

So I had to  reinstall half of the software which was supposed to work out of the box, installed/updated the other half using RedHat Network, and at the end of the day, when I though I have everything working, and moved one of my sites to test on the new system, I started to get seg faults here and there, and the system went pretty unstable.

So, tomorrow I'll just reinstall the whole OS, leaving most the RedHat-supplied stuff off - and will get a 100% working and controllable system with 100% probability.

What I don't understand is - is it me who just doesn't know how to build stuff on top of pre-built stuff, or is it RedHat's approach to installs, oriented to "average user" sort of system admin? Oh well.. one day of work lost, but lessons were learned :)

I have no idea why you would need them, but I just spent the best half of day trying to compile Subversion from the source of some ancient RHL 7.3 machine - the operation which usually takes a few minutes, but I was getting errors no matter what. Luckily, I found RPM repository which contained everything I needed to install Subversion of that ancient RedHat machine.Here's the link:http://summersoft.fay.ar.us/pub/subversion/1.1.4/redhat-7.x/bin/ 

.. is a new server of course :)

Though I'm not much of a full-fledged SA, and just have to do it because nobody else in the company where I work at, can.. Still, there was a very warm and fuzzy feeling when I was unpacking our new Dell PowerEdge 1900 servers (well, only one of them because I'll do setup next month).

These actually are the first "real" servers which I'll be setting up and administering myself (there were lots of built-it-yourself servers before.. I wonder how they match against the "real" ones)

I'll be setting up separate application and database servers.. The specs are as follows:

Application: Intel Xeon Quad 2.33MHz, 8Gb RAM, RAID10 (6×250Gb), DRAC5 remote access card, Intel's Dual 1Gb Ethernet, RedHat 4.5

Database: Intel Xeon Quad 1.86MHz, 4Gb RAM, RAID10 (6×250Gb), DRAC5, Intel Dual 1Gbit Ethernet, RedHat 4.5

Well we don't yet even have a server room, closet, or anything.. Lots of things to setup, even more stuff to learn.

Here's a quick tip if you're getting errors like this one in your Rails application:

/usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/action_controller/session/active_record_store.rb:84: [BUG] Segmentation fault

The most probable reason you're getting the Segmentation fault and your server crashes is because you're trying to store too much data in sessions table of your application (I assume you are using active_record_store as a session store).

The problem with "too much data" is that by default, the session table creation rake task created the following migration in Rails 1.x:

class AddSessions < ActiveRecord::Migration
def self.up
create_table :sessions do |t|
t.column :session_id, :string
t.column :data, :text
t.column :updated_at, :datetime
end
add_index :sessions, :session_id
end

def self.down
drop_table :sessions
end
end

Please note the data field defined as text. This means that it can only store up to 64Kb of data. And that also means that if you're trying to store more than 64Kb in your session.

In order to fix the problem, you just need to manually change the column type before you run migration which creates session store, or just create a new migration which changes parameters of the data column in existing sessions table:

Should look something like that (Rails 2 syntax):

class CreateSessions < ActiveRecord::Migration
def self.up
drop_table :sessions

create_table :sessions do |t|
t.string :session_id, :null => false
t.column :data, :binary, :limit => 10.megabyte
t.timestamps
end

add_index :sessions, :session_id
add_index :sessions, :updated_at
end

def self.down
drop_table :sessions
end
end

Empty your sessions table, restart your server and you're done. No more segmentation faults. Of course you shouldn't store that much data in a session in the first place, but well.. things happen. Now I'm off to fix my code which stores Megs of data in a session store ;)