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Old 12-21-2009, 11:51 PM
Marc Aymerich
 
Default Framework for web control panel.

Hi everyone,
I'm planning to write a web control panel & billing system from
scratch. The project is for a little NGO ISP that offer hosting, mail,
VPS... Yeah, I know there are a lot of projects that do that, but
really we need to develop our panel from scratch. I planned to start
with a framework but is difficult to chose one (Yii, django, pylons,
ror...). The language doesn't matter (php, python, ruby..), we really
need fast development, extensible and maintainable code, and good
integration with MySQL.

I really appreciate your opinions and recommendations
Thanks a lot!
Marc


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Old 12-22-2009, 01:36 AM
Shane Chrisp
 
Default Framework for web control panel.

Marc Aymerich wrote:

Hi everyone,
I'm planning to write a web control panel & billing system from
scratch. The project is for a little NGO ISP that offer hosting, mail,
VPS... Yeah, I know there are a lot of projects that do that, but
really we need to develop our panel from scratch. I planned to start
with a framework but is difficult to chose one (Yii, django, pylons,
ror...). The language doesn't matter (php, python, ruby..), we really
need fast development, extensible and maintainable code, and good
integration with MySQL.

I really appreciate your opinions and recommendations
Thanks a lot!
Marc




Hi Marc,

Good luck with the project. These things generally have a habit of
running away
with both times and costs and fast become a nightmare to maintain due to
the
goal posts which stand still. It is generally a lot cheaper and simpler
to find an
off the shelf product, even a commercial one. With that said, if your
still willing

to move forward, take a look at Zend Framework
http://www.zend.com/en/community/framework

Shane


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Old 12-22-2009, 02:30 AM
Thomas Goirand
 
Default Framework for web control panel.

Marc Aymerich wrote:
> Hi everyone,
> I'm planning to write a web control panel & billing system from
> scratch. The project is for a little NGO ISP that offer hosting, mail,
> VPS... Yeah, I know there are a lot of projects that do that, but
> really we need to develop our panel from scratch.

Why?

Thomas


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Old 12-22-2009, 05:41 AM
Marc Aymerich
 
Default Framework for web control panel.

On Tue, Dec 22, 2009 at 3:36 AM, Shane Chrisp <shane@2000cn.com.au> wrote:
> Marc Aymerich wrote:
>>
>> Hi everyone,
>> I'm planning to write a web control panel & billing system from
>> scratch. The project is for a little NGO ISP that offer hosting, mail,
>> VPS... Yeah, I know there are a lot of projects that do that, but
>> really we need to develop our panel from scratch. I planned to start
>> with a framework but is difficult to chose one (Yii, django, pylons,
>> ror...). The language doesn't matter (php, python, ruby..), we really
>> need fast development, extensible and maintainable code, and good
>> integration with MySQL.
>>
>> I really appreciate your opinions and recommendations
>> Thanks a lot!
>> Marc
>>
>>
>>
>
> Hi Marc,
>
> Good luck with the project. These things generally have a habit of running
> away
> with both times and costs and fast become a nightmare to maintain due to the
> goal posts which stand still. It is generally a lot cheaper and simpler to
> find an
> off the shelf product, even a commercial one. With that said, if your still
> willing
> to move forward, take a look at Zend Framework
> http://www.zend.com/en/community/framework
>
> Shane

Hi Shane,
Now I'm downloading Zend to try it

My pretension is not to do a large project, only a billing system that
permits to keep up to date the services contracted by the users and
invoicing then when needed. And on the part of the control panel, we
don't have the need to be able to do a lot of things. We'll add new
features until we get bored.

On Tue, Dec 22, 2009 at 4:30 AM, Thomas Goirand <thomas@goirand.fr> wrote:
> Marc Aymerich wrote:
>> Hi everyone,
>> I'm planning to write a web control panel & billing system from
>> scratch. The project is for a little NGO ISP that offer hosting, mail,
>> VPS... Yeah, I know there are a lot of projects that do that, but
>> really we need to develop our panel from scratch.
>
> Why?
>

Hi thomas,
After checking a lot of panels (DTC, SysCP, ISPConfig, ...) I can say
that the most important reason is that our members can use our domain
and subdomains of it for his web pages. (Like this: user.ourdomain.org
or ourdomain.org/user). This seems silly but breaks with the schemes
of most panels.
In the second place we need a web panel with billing system. This
discard 70% of the panels. moreover we are a NGO and we have a
membership quotas, exempt of taxes, that includes some services, but
otherwise, some members require special services like VPS or a big
development on his web page, in that case they have to pay with taxes.
This is not difficult to implement but adds more work.
Finally, the most panels are designed for environments where all
services are in the same server, we have the services spread over
multiple servers. Yes, I know that is possible take any of the
existent panels and with some modifications we can adapt it to our
system. but anyway the data migration, system adaptation and panel
modifications sure that will take a lot of work. I think that we can
invert this effort to do a good database and simple web interface, and
slowly add the functionalities. Thats what I'd prefer as i enjoy doing
this kind of things

> Thomas
>


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Old 12-22-2009, 02:41 PM
Thomas Goirand
 
Default Framework for web control panel.

Sorry if I preach for my own church here, but I truly think you are
mislead herel!

Marc Aymerich wrote:
>>> Hi everyone,
>>> I'm planning to write a web control panel & billing system from
>>> scratch. The project is for a little NGO ISP that offer hosting, mail,
>>> VPS... Yeah, I know there are a lot of projects that do that, but
>>> really we need to develop our panel from scratch.
>> Why?
>>
>
> Hi thomas,
> After checking a lot of panels (DTC, SysCP, ISPConfig, ...) I can say
> that the most important reason is that our members can use our domain
> and subdomains of it for his web pages. (Like this: user.ourdomain.org
> or ourdomain.org/user). This seems silly but breaks with the schemes
> of most panels.

Well, it does work with my panel (DTC) without any issue, I know many
hosts using this functionality. You just add subdomain.example.com as if
it was a domain like example.com and everything works as expected (like
emails@subdomain.example.com, etc.). There's even everything needed at
registration time so you can register the subdomain of example.com if
you like it this way.

> In the second place we need a web panel with billing system. This
> discard 70% of the panels.

Not DTC, it has it (customizable email reminders in multiple languages,
pdf invoices, multiple payment gateways, etc.).

> moreover we are a NGO and we have a
> membership quotas, exempt of taxes, that includes some services, but
> otherwise, some members require special services like VPS or a big
> development on his web page, in that case they have to pay with taxes.

Tweaking the billing system just for taxes reasons could be a nice
contribution, it's not an argument to start everything over from scratch
(unless you'd like to bill that NGO a lot of money for years of
developments...).

In the case of EU NGO, I see no reason why what we did wouldn't fit,
they are subject to the same tax system as other entities (that is, VAT
is to be paid in the country of the payee if he has a VAT number). In
USA, there's no VAT on internet services. What is your case, I don't get it?

If it's for billing big developments, then you can use a "fake"
dedicated server, I do that often (or of course, make invoices by hand,
it wont kill you if it's few times a year for a very long dev. and big
contracts).

> Finally, the most panels are designed for environments where all
> services are in the same server, we have the services spread over
> multiple servers.

I read about this motivation many times, however, there are very rare
cases where the load makes it a real need. In such case, you typically
run a single website, and then using a control panel isn't really
justified, as you would run only apache and a single vhost per server,
and maybe a reverse proxy like HAProxy to do the balancing. In all other
cases, running all on the same server reduces so much complexity that
it's the best choice to make.

Lets consider this:
- Running a MySQL service over network adds a lot of latencies and
issues, will load your switch, etc. (the one that will pretend that
running over Ethernet is faster than a Unix socket is just plain wrong).
So you want to avoid this if possible, especially if you don't have
enough load to need lets say 3/4 MySQL servers is master/slave mode.
- Then you may say you want to run DNS on another server as well, but
you will also have to run a DNS server on the apache and mail server to
speed-up resolving (caching name server).
- You will also be running a mail server on all of your servers to at
least receive mail for root.

All together, this will NOT improve security, as all daemons (apart web)
will end up running on all servers anyway so this is not an argument. In
fact, you will just end up increasing complexity for no valid reason.

So what are your other arguments for running in multiple servers instead
of just one?

Anyway, with a very small modification to the cron job to run only
selected tasks, and an NFS mount for /var/www in your high performing
NAS, DTC can do that as well. Tweaking it so that it is really
implemented by default fully shouldn't take so long (and I'd be happy to
help you do that).

> Yes, I know that is possible take any of the
> existent panels and with some modifications we can adapt it to our
> system. but anyway the data migration, system adaptation and panel
> modifications sure that will take a lot of work.

I think you are really under-estimating the programming work here.
There's nothing really complicated, just YEARS of work, literally. Be
prepared to having half of the needed functions in 2 or 3 years of time.
In the past, I heard so many people pretending that they would write
such a panel, but at the end, only a handful ended with something that
practically does what it is supposed to be, because its just too much work.

> I think that we can
> invert this effort to do a good database and simple web interface, and
> slowly add the functionalities. Thats what I'd prefer as i enjoy doing
> this kind of things

If your only argument is that you will enjoy doing it, then great! I do
also love doing this programming. But otherwise, there's no rational
here, unless charging your customer for years of development.

Thomas


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Old 12-22-2009, 10:03 PM
Robert L Mathews
 
Default Framework for web control panel.

Thomas Goirand wrote:


I think you are really under-estimating the programming work here.
There's nothing really complicated, just YEARS of work, literally.


Agreed. I wrote the custom control panel for our hosting company. The
project started over ten years ago and now contains over 30,000 lines of
Perl (yes, really, and I'm a good programmer), and although it's good
software, it still doesn't have all the features I want.


The reason I started doing it myself ten years ago was that all the
alternatives were awful at the time, which is no longer true. If I were
starting from scratch now, I wouldn't even remotely consider writing it
myself.


--
Robert L Mathews, Tiger Technologies, http://www.tigertech.net/


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Old 12-23-2009, 01:59 PM
Kris Deugau
 
Default Framework for web control panel.

Thomas Goirand wrote:

I read about this motivation many times, however, there are very rare
cases where the load makes it a real need. In such case, you typically
run a single website, and then using a control panel isn't really
justified, as you would run only apache and a single vhost per server,
and maybe a reverse proxy like HAProxy to do the balancing. In all other
cases, running all on the same server reduces so much complexity that
it's the best choice to make.


Unless you've got enough hosting customers that one physical machine
can't handle all those sites, never mind the added memory load of a
leaky hog like BIND, plus the load of dealing with all the spam that
inevitably comes in to the one customer who *insists* on using a
catchall account. (Never mind the mail load for the other 999 customers.)


I've done this dance of trying to wedge everything into one box. Even
on a very small scale (~40 domains, at a time when spam was only ~10% -
if that - of the overall mail volume), it works for a while, but sooner
or later something will blow up and *all* services for a bunch of
customers will go down. (Give them a pile of hemp strands, and some
customers *will* industriously go about making a rope to hang themselves
with... and in a fully shared-hosting all-in-one environment, they may
well take a lot of others with them.)



- Running a MySQL service over network adds a lot of latencies and
issues, will load your switch, etc. (the one that will pretend that
running over Ethernet is faster than a Unix socket is just plain wrong).
So you want to avoid this if possible, especially if you don't have
enough load to need lets say 3/4 MySQL servers is master/slave mode.


I'd say GigE latency is not an issue compared to running the server into
swap because someone fired off a messy query. Ethernet might not be
faster than a Unix socket, but running your database traffic to the next
machine down the rack over the second gigabit port on a private (V)LAN
reserved for just such traffic is really unlikely to be slower than
trying to share out RAM sanely between your database processes and web
traffic.



- Then you may say you want to run DNS on another server as well, but
you will also have to run a DNS server on the apache and mail server to
speed-up resolving (caching name server).


Mmm, not quite IME. A caching server is different from an authoritative
server, and most best-practice documents I've seen say you shouldn't mix
the two.


Which means your authoritative zones shouldn't be local to the DNS cache
on the web server. There's also the issue of distributing the
authoritative data to a second machine anyway - no DNS system I've used
knows how to distribute new zones to another server automagically. (I
know there *are* a few, but IIRC the overhead is far greater than you'd
gain by running full DNS on every box.... and most rely on, yep, an SQL
database backend.)


FWIW, here we seem to getting along fine with our servers (10 that I can
think of offhand that *need* responsive DNS service) all using the same
two dnscache servers as our connectivity customers (dialup, DSL, cable,
fibre, wireless, and various copper loop services). Two of our four
authoritative tinydns servers happen to be on the same physical machines
as the caches (largely due to power capacity issues, IIRC), but they
could just as well be separate machines; the caches don't have any
special knowledge about the authoritative zones.



- You will also be running a mail server on all of your servers to at
least receive mail for root.


mmmnope. nullmailer forwarding everything to a proper role account
mailbox (or alias) is all you need (although nullmailer needs to be
kicked once in a while IME). You *really* don't want to have to log
into every single box to receive cronspam and other administrivia.
(I've been there. It doesn't scale well beyond two or three machines.)


Further, load spikes on one service can affect any others; if you have
physically separate boxes for different services, your authoritative DNS
won't stall out when you get a flood of spam coming in, and a sudden
order-of-magnitude spike in web traffic to one site (linked from eg
slashdot) won't kill your POP mail service (and SMTP, and webmail...).



I think you are really under-estimating the programming work here.
There's nothing really complicated, just YEARS of work, literally. Be
prepared to having half of the needed functions in 2 or 3 years of time.
In the past, I heard so many people pretending that they would write
such a panel, but at the end, only a handful ended with something that
practically does what it is supposed to be, because its just too much work.


I have to agree with this. I wrote a simple set of scripts to manage
virtual hosting at one time, but the interface was pretty simpleminded.
It was functional enough for a small ISP (~1500 dialup customers and a
bit of domain hosting), and I opened the email management for domains to
customers (add, remove, change password, change forwarding), but it
still lacked a few things on the internal side (delete domain, make
changes of any kind to DNS after initial domain addition), and never got
integrated with any of the billing.


Our current billing system has been in use for a couple of years, after
several years in development (and, IIRC, one false release some time
before it really got put into full use), but it's *still* under active
development - of course, it has to cope with all the new services we
keep adding on as we buy smaller ISPs. <G>


On the other hand, it's only in the last 6 months or so that it's had
any visibility into email accounts for hosted domains.


And this is with a more or less dedicated group all working on various
aspects of the billing/recordkeeping side of the system - and another
few people working on automation and scripting on the mail servers.


-kgd


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Old 12-23-2009, 08:09 PM
Thomas Goirand
 
Default Framework for web control panel.

Kris Deugau wrote:
> Unless you've got enough hosting customers that one physical machine
> can't handle all those sites

Then open a 2nd server and move customers around, not a big deal.

> never mind the added memory load of a
> leaky hog like BIND

Totally unrelated, and frankly, stuffs like bind are always pointed as
bad and having issues, but this is really because everyone is using it,
so we hear about issues very loudly and fast. I never had any issue with
it myself.

> plus the load of dealing with all the spam that
> inevitably comes in to the one customer who *insists* on using a
> catchall account. (Never mind the mail load for the other 999 customers.)

That's were monitoring comes handy and very important. A shared host
without a good monitoring solution quickly becomes trashy. Separating
your server into multiple ones will NOT solve this issue anyway. You
should be able to point directly at that customer and let him migrate to
a VPS or a dedicated if he is taking all the resources. And by the way,
we never had issue with catchall either...

> I've done this dance of trying to wedge everything into one box. Even
> on a very small scale (~40 domains, at a time when spam was only ~10% -
> if that - of the overall mail volume), it works for a while, but sooner
> or later something will blow up and *all* services for a bunch of
> customers will go down.

In years of hosting, this never happened to me, even with thousands of
domains installed. Maybe your anti-spam system is inefficient and/or is
not caring enough about load issues. The things we implemented are (in
the order of blocking in the mail queue):
- iptable incomming connection rate limiting (otherwise, it goes BOOM
very fast, indeed).
- Basic domain checking (is an existing domain, has a valid MX, etc.)
- Basic reverse DNS checks (PTR doesn't contain DSL, DHCP, or the like...)
- RBL check (spamhaus)
- SPF check, if SPF has a hard fail, block, if soft fail, greylist the
incoming email (all this done with tumgreyspf that I maintain in Debian)
- DKIM check (using dkimproxy that I maintain in Debian)

THEN comes the heavy stuffs like amavis, clamav, and spamassassin. If
you do things this way, then everything goes smoothly.

>> - Running a MySQL service over network adds a lot of latencies and
>> issues, will load your switch, etc. (the one that will pretend that
>> running over Ethernet is faster than a Unix socket is just plain wrong).
>> So you want to avoid this if possible, especially if you don't have
>> enough load to need lets say 3/4 MySQL servers is master/slave mode.
>
> I'd say GigE latency is not an issue compared to running the server into
> swap because someone fired off a messy query. Ethernet might not be
> faster than a Unix socket, but running your database traffic to the next
> machine down the rack over the second gigabit port on a private (V)LAN
> reserved for just such traffic is really unlikely to be slower than
> trying to share out RAM sanely between your database processes and web
> traffic.

If you experience this, then it means you didn't configure the limits of
MySQL correctly, and allowing your customers to do dangerous things.
This will NOT change anyway if the server is remote, that server will
ALSO be loaded like crazy, and this WILL affect all other sites (as most
of them will also run MySQL). Again, tight monitoring and rules
enforcing is the solution here.

>> - Then you may say you want to run DNS on another server as well, but
>> you will also have to run a DNS server on the apache and mail server to
>> speed-up resolving (caching name server).
>
> Mmm, not quite IME. A caching server is different from an authoritative
> server, and most best-practice documents I've seen say you shouldn't mix
> the two.

First time I hear about this! Why is that?

> There's also the issue of distributing the
> authoritative data to a second machine anyway - no DNS system I've used
> knows how to distribute new zones to another server automagically. (I
> know there *are* a few, but IIRC the overhead is far greater than you'd
> gain by running full DNS on every box.... and most rely on, yep, an SQL
> database backend.)

Are you talking about the *zone list*, eg, the list of domain name?
Well, that's quite a trivial thing to write in a control panel...

> Further, load spikes on one service can affect any others; if you have
> physically separate boxes for different services, your authoritative DNS
> won't stall out when you get a flood of spam coming in, and a sudden
> order-of-magnitude spike in web traffic to one site (linked from eg
> slashdot) won't kill your POP mail service (and SMTP, and webmail...).

Unlikely to happen if you do incoming connection rate limiting for SMTP
(using iptables), and use mod_bwshare and mod_cband for apache. Again,
the issues you are having on a single server, you will have them on
multiple servers as well, you are just mitigating the consequences here,
not eliminating the issue, which you shouldn't be.

Thomas


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Old 12-23-2009, 09:22 PM
Adam McGreggor
 
Default Framework for web control panel.

On Thu, Dec 24, 2009 at 05:09:51AM +0800, Thomas Goirand wrote:
> In years of hosting, this never happened to me, even with thousands of
> domains installed. Maybe your anti-spam system is inefficient and/or is
> not caring enough about load issues. The things we implemented are (in
> the order of blocking in the mail queue):
> - iptable incomming connection rate limiting (otherwise, it goes BOOM
> very fast, indeed).

Do you mind sharing your config/the rule-set that you're using?
Obviously, the fine-tuning will be up to individual
mail-admins/postmasters, but roughly speaking?

Do you trust all hosts the same (and rate-limit accordingly), or are
you less/more fierce/strict with some hosts?

--
``Sir Humphrey: Well, you're a banker, surely you read the Financial Times?'
``Sir Desmond: Can't understand it. Full of economic theory.'
``Sir Humphrey: Why do you buy it?'
``Sir Desmond: Oh, you know, it's part of the uniform.'


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Old 12-24-2009, 05:24 AM
Thomas Goirand
 
Default Framework for web control panel.

Adam McGreggor wrote:
> Do you mind sharing your config/the rule-set that you're using?
> Obviously, the fine-tuning will be up to individual
> mail-admins/postmasters, but roughly speaking?

All what we do is published in our control panel, including the iptables
rules in our dtc-dos-firewall (included in Debian, but I suggest you to
get the latest in our debian repo, or have a look on our gitweb). All
rates are configurable through a config file in /etc/dtc.

> Do you trust all hosts the same (and rate-limit accordingly), or are
> you less/more fierce/strict with some hosts?

I trust that for each type of server hardware, there are limits that you
should enforce in order to not have your server blow up. What is written
in the package as default works in most cases though, for an average
actual dedicated server, but it's best to tweak it. For example, for the
SMTP receiving, you should have a look at the amount of email you are
receiving on average (we use mailgraph to know that), and then set it to
something like 4 or 5 times that amount to be able to handle peak
connections. In some cases, best might be to do the opposite way:
enforce something restrictive, then relax until nobody complains
anymore. That's what we did for mod_bwshare. The following parameters
for mod_cband wont be annoying in most cases:

<Directory />
BW_tx1debt_max 500
BW_tx1cred_rate 0.95
BW_tx2debt_max 6000000
BW_tx2cred_rate 50000000
</Directory>

One more thing. Our iptables script is being quite restrictive with the
number ssh connections. In some cases, this can be dangerous because if
someone does constant connections, you wont be able to log into your
server. We don't care as we have KVM over IP on all our servers, so if
someone does that, we still got access. It's extremely important to do
this with sshd, as it forks quite fast and can die or fill up the memory
quickly, like many other daemons.

Here's a link to our script in the latest entry of our Git (quite a
moving target, so this is valid for this week only! ):

http://git.gplhost.com/gitweb/?p=dtc.git;a=blob;f=debian/dtc-dos-firewall.init;h=4b2c8f8e4e2bd97df6fa2c03750df4e3d2 cd4abf;hb=1b87a31e25fa21bc8904f20500d984b6e57d479c

I believe that the version for Xen servers is a way better though:

http://git.gplhost.com/gitweb/?p=dtc-xen.git;a=blob;f=debian/dtc-xen-firewall.init;h=afdabffdc4a0903268dc4d60864f1496de b4127f;hb=56186fb53cd70a66fef23bb61bddbb7efc3e6170

Note the REJECT vs LOGDROP thing. The nice thing with LOGDROP is that
you will see in syslog what's happening whenever someone abuses. Droping
packets is quite a nice thing to do, especially for SMTP and web
servers, because what's going to happen is that the client will keep
trying for a while before timing-out and give up. This is not always
wanted though, like for ssh where we decided that REJECT was ok.

Contributions are obviously welcome, all this is quite basic, I'm not
particularly proud of it, but it does its service protection job.

Thomas


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