Topic: Deferred outgoing email - is it possible?

[gbentley]

Hi, we have an SME on the LAN and a single ADSL serving 20 PC's - there is a lot of email and drawing attachments making up MB of email data traffic to our ISP mail relay that sometimes kills the connection for anything else (upload speeds are in order of .3 to .5 MB)

Is it possible to deferr outgoing / relayed email at all?

Was thinking if we did this once on the hour everyone would know to avoid those times for surfing?

[janet]

gbentley

qmail will utilise all available bandwidth if allowed, meaning it will send as many email messages as possible at the same time (concurrently). IIRC the default is 40

The simplest answer is to throttle the concurrent number of outgoing connections
eg
config setprop qmail ConcurrencyRemote 5
signal-event email-update

Adjust the number of connections to suit your requirements, you may need to experiment to find a happy compromise between speed of sending & receiving messages and web browsing speed etc.

check with
config show qmail

[CharlieBrady]

Hi, we have an SME on the LAN and a single ADSL serving 20 PC's - there is a lot of email and drawing attachments making up MB of email data traffic to our ISP mail relay that sometimes kills the connection for anything else (upload speeds are in order of .3 to .5 MB)

You can suggest to your users that they use one of the many sharing websites (dropbox, pastebin, google docs, whatever), and just post a link via email.

[Stefano]

or, if your SME is not in server and gateway mode, use a firewall to make some trafic shaping and sharing files via an ad hoc ibay (I usually do this way.. no need for additional sw on the clients, simple cut and paste files into /files dir and instructions to the monkeys...)

[gbentley]

Thanks all for suggestions

[janet]

gbentley

To actually control/limit/share the outgoing bandwidth, look at the wondershaper Howto which AFAIK works OK.
Otherwise try the wondershaper contrib, but I think the current contrib(s) are not working correctly, refer bugzilla & the Howto.

Please report back your outcome, I am interested if the suggestions resolve your issues.

[gbentley]

thanks janet - tbh I am only using the box for a local mail server [not proxy / gw etc] so at a brief look dont think this would help me. May look into the router config see how flexible it is.

[purvis]

Even tho your server is not in gateway mode, you can use the SME server for a web proxy for browsers on your workstations. This should cache some of your web activity. How effective. I do not know. The dns lookup should be cached as well and you will also benefit from the excellent networking efficiency that linux has built in too.

[janet]

gbentley

I am only using the box for a local mail server [not proxy / gw etc] so at a brief look dont think this would help me.

If the server is not the gateway then shaping will not help much on that server, you have to do that in the gateway/router

The qmail settings I advised
ie
config setprop qmail ConcurrencyRemote 5
signal-event email-update
will definitely slow down (or defer) the mail & the result is less bandwidth usage at any point in time, which is essentially what you requested, try it & see, it will only take 2 minutes to implement.
To return to standard settings do
config delprop qmail ConcurrencyRemote
signal-event email-update

which just allows the templates to use the default value (40) when there is no other value specified in the config database

[gbentley]

Thanks Janet - I did this as soon as I read your message - am not on site so need to get feedback from the office.

[Stefano]

I would say that sending BIG attachment with email is definitely a bad practice

email is not a file sharing protocol/tool

gbentley: I would publish an ibay with no php and sent email with simple link to the file

[gbentley]

Depends what you mean by big - drawings are typically 8-10MB but there are multiples and there are 20 odd staff doing this regular. So when the server is relaying, our poor .4 mb upstream is somewhat hampered.

This is also the case if staff use dropbox or upload via FTP to our webspace.

[CharlieBrady]

gbentley: I would publish an ibay with no php and sent email with simple link to the file

That won't necessarily help with the problem. That might mean that instead of sending 20copies of the file there would be 20 external users fetching the file. Still 20 file transfers taking place.

My suggestion to use an external site would mean one push to that site, then 20 fetches from that site from other places, hence only one transfer on the customer's limited link.

[Stefano]

a single mail with a 10 MB attach is, IMHO, big enough..

on all my servers I reject email bigger than 10/12 MB

since I guess you have a router/firewall in front of your SME, work on it.. even the cheapest one, nowadays, support band shaping

HTH

[purvis]

Only a few years back i had 2 dsl services coming into one location.

I did this to set up two networks. One dsl for a set of computers to access the internet from one wireless lan and another dsl to support a wired office to do all the other stuff. This was the only way i knew how keep some peace in the office. I did not double nat my routers and i knew nothing of double natting.

What was really crazy, was that originally i had 5 analog lines coming in to the location with one line having dsl service. I had my dsl service on the same line as our 5 line(the fax).
I ordered a new 6 line(the office staff had grown)  with a dsl connection.
Can you believe the 6 line with 2 dsl connections was cheaper than 5 lines with one dsl connection.
Bellsouth at that time had a price break on after having 5 lines.
It was just crazy to add a line and dsl and be paying 75 dollars less. I would of order 6 lines just to have a lower bill in the first place if i had know that.

My point, look into the priceing of your services. Getting more may cost you less.
If you are on a T1 line and that is causing your low upstream. You may be able to reduce your number of phone lines, there by increasing your internet speed and put one or more magic jack lines to use the internet.
Ps we are saving 17,000 dollars per year now by using one or two magic lines in all offices. All long distance phone calls are made on them.

There are routers that do have dual wan connections if you want to go with two dsl connections or you can still have a second dsl and use that as an internet gateway for web browsing.
For 20 people with slow internet, a second internet(dsl) connection or even a third connection would seem economical for most locations in the world with 20 people making use of the services.
 

[gbentley]

@purvis - you must be able to read the matrix!

Just been looking at various options on second line / dsl service as well as devices.

http://www.thinkbroadband.com/hardware/reviews/44-neteyes-cyclone200.html

http://www.amazon.co.uk/Peplink-Balance-20-Dual-WAN-Gigabit/dp/B0042210U6

http://www.draytek.co.uk/products/vigor2920.html

The support on the last link have been quite helpful - I had read somewhere that some devices cannot balance upstream data? Here was the reply about session based load balancing;

"A 'session' might be one activity that a client PC is doing, for example, downloading a file, viewing a web site. If a PC downloads a file and then watches a video (both from the Internet) then the load balancing will put the filedownload request down one WAN connection and the video down the other.

By default, the router will split sessions equally but you can set up rules if you prefer (e.g. email always goes down WAN1 etc.).  Therefore, you don't have to do any setup if you are happy with the default arrangement."

Oh, nearly forgot - BT in the UK have not advertised this, but there seem to have been some sites where they have increased the upstream to almost a meg! Whilst its not much its better than the average I have seen of about .5 mb

[gbentley]

since I guess you have a router/firewall in front of your SME, work on it.. even the cheapest one, nowadays, support band shaping

Its a NG DG834 - I have scoured the interface and it seems quite basic but I have been considering creating outbound rules and logging for only specific services, rather than just 'default all' - in an attempt to understand our data output.

[purvis]

I had just come across this webpage and thought it might be of some use on achieving  a faster web experience using slow internet connections. I will let the reader interrupt the webpage.
http://www.die.net/musings/page_load_time/

[purvis]

I have use some of the NG fvs124g routers for years.

http://www.downloads.netgear.com/files/GDC/FVS124G/FVS124G_RM_30Mar05.pdf
There are newer models.

[purvis]

gbentley

You might want to look into celluar internet service too as an additon.
It can be amazing how much faster it is compared to dsl.
A few years ago, I tethered my iphone 3gs to an apple macbook pro laptop computer by way of a usb connection and rebroadcast the internet connection using the same apple computer out the  built apple's airport wireless network connection, there by making my apple a gateway(wireless hot spot).
I could have made the apple's wired connection the gateway.
This was all to easy to do.
I always thought my iphone was slow because of the internet. It was the iphone itself was slow.
The speed thru the iphone was faster than our offices internet connection.
Now i have an iphone 5 with 4g. The speed of downloads and uploads is so fast, it is just crazy.
I had an unlimited internet usage on my phone then and my brother who does the cellular phone management dropped everybody's internet data plan  to save 350 dollars a month by putting all our celluar internet data service on a large shared data plan unknowing the result on my phone. But it is saving a lot of money each year, because I did not really need that unlimited plan.
But look into cellular internet service if you do not have other good choices.

[purvis]

gbentley
You can also do this.
At dyndns.com they offer a service called dyn email backup mx.
What this service does is catch all your email while your email server is down.
I used this service once at one office location where a email server was at because our internet service was going in and out.
Yes it was the internet service provider's  fault due to some glitch in they network. They finally fixed it after a year. Drove me crazy working on it.

But here is a thought for you.
It is thinking out the box like i have always HAD to do to fix problems.

I am not suggesting you do this but with some others input it might be a work around for you.
Like you said, is there a way to pause email.
here goes
If you have a bash script that is run in the cron.hourly directory.
You should be able to start and stop the email services of sending or receiving emails at the times you choose.
You can have the email services running all night and other odd days such as weekends.
During the day, you can start,stop,suspend those services on a schedule.
When you stop/suspend the email service, the dyn email backup mx should catch your receiving emails and deliver them when you email service is back running.
Of course you have figure all this out. But for any troublesome internet connection, this might work.
I have used dyndns.com for all my services. There are cheaper services out there but i have to give them a gold star on service and support.

[purvis]

gbentley

Also internet access activity by a workstation can be overwhelming these days.
If you can figure out a way of blocking a workstation to certain sites(googleanalytics, advertising, etc) or certain programs accessing to certain sites at different times of the day.
That would also reduce your internet activity.

Here are some things to help you do that.
Use a proxy server and block those sites.
Use a proxy server on each the local workstation and block sites using the power of the workstation rather than a dictated server or router(blocking sites by router will slow your router down) to stop internet access to those sites.
Use toplang.com Internet Lock to block certain program from accessing the internet or block certain program from having access to the internet by time.
Toplang gave me a very good rate on bulk purchase and the program works and Internet Lock does not slow my workstations down.

[gbentley]

Am using OpenDNS free service to block certain sites and stop staff wasting time. In truth they are mostly well behaved people who are driven to get work done on design / CAD and dont waste time surfing. Over the last 2-3 years the amount of work processed via email has probably increased 3 fold and I would say that 90% of their comms is email. They do however have to use planning portals which involve and interactive selective upload session again adding more traffic to their upstream. At times surfing is perfectly acceptable, others its dog slow or stop. And of course because of the random nature of peoples behaviour its hard to say when its going to be usable.

I thank you for your suggestions though. Just today I have seen the results of putting in a request for uncapping the upstream. We are now getting .864 mb up and it already feels better doing remote admin! Will know by the end of the day whether the rest of the office 'feel' any difference.

Out of interest we are with www.plus.net in the UK - on a standard business account.

[purvis]

Your dsl is much faster up and down than ours was and your prices seem to be much less. I do not know what a line cost though.  We are on cable now.