Koozali.org: home of the SME Server

sme9.2 alternative Internet access via 4G wireless modem

Offline raem

  • *
  • 3,972
  • +4/-0
sme9.2 alternative Internet access via 4G wireless modem
« on: October 15, 2018, 09:34:57 AM »
Dear All

Can someone help with advice, suggestions etc.
I am in southern half of Sydney Australia.
In my small office I have a sme9.2 in server gateway mode, using a bridged modem on TPG ADSL2+ with a Telstra phone line. Phone cable was cut 1.5 weeks ago & Telstra say another week or more to fix it. I was overseas in USA for half of last week so missed out on some of the disruption.

My business uses Internet continuously. I have ten Windows 10 Pro workstations in a trusted DOMAIN & do not like to change anything around.

I am thinking to temporarily setup a 4G wireless modem to provide Internet to the LAN connection on hub, or maybe reconfigure the server for a Static connection & connect the Ethernet output of the modem to the server WAN Ethernet input.

I never had this sort of problem in over 10 years using ADSL so have no backup plan for a failed Internet connection.

One concern was that the 4G SIM card would support the required services eg mail server, web server, ssh access. The TPG ADSL service did not block any ports or services so I am hoping the SIM card will provide similar functionality.
Looking to use an Amaysim data only SIM plan (uses Optus 4G).

Can anyone comment or give advice if this is going to work OK etc.
The main things we are missing is Internet access & non receipt of domain name based email messages. Mails are bouncing back to the senders as there is no connection to the mail server (due to cut cables). Ouch ! Approx 600 Telstra customers are affected.

Only low volume & small amounts of traffic except for Windows updates etc.

Other suggestions or ideas for a temporary fix are appreciated.

Thanks
Ray
...

Offline mmccarn

  • *
  • 2,626
  • +10/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #1 on: October 15, 2018, 01:19:44 PM »
One concern was that the 4G SIM card would support the required services eg mail server, web server, ssh access. The TPG ADSL service did not block any ports or services so I am hoping the SIM card will provide similar functionality.
Looking to use an Amaysim data only SIM plan (uses Optus 4G).

You would have to find another Amaysim customer in your local area who is also running his own mail server to be 100% sure that things will work.  Their sales folks *might* give straight answers by phone or chat online.

With the exception of SMTP traffic on port 25 I would not expect them to be blocking anything -- most early adopters are tech folks who would need to be able to make connections on random ports.

SMTP traffic on port 25 is a different issue, and may be blocked: outbound (because they don't want customers sending SPAM from their IP block), inbound (because they don't want customers hosting their own mail servers), or both.

If SMTP traffic is blocked would have to reconfigure your SME to relay outgoing mail through a smarthost somewhere to handle outgoing email, and you might need to configure an external mail service to collect your email then reconfigure the SME to use 'fetchmail' go get your mail from the external server.  Amaysim sales/support should be able to tell you if you can host your own mail server behind their service.

If it turns out that Amaysim is blocking ports that you need for your SME server, you could possibly setup Amaysim at the office for your Windows users, but move the SME server physically to another location where the internet still works.  (This, of course, introduces a host of other technical issues -- but your email would work...).

Good luck.

Offline TerryF

  • grumpy old man
  • *
  • 1,821
  • +6/-0

Offline raem

  • *
  • 3,972
  • +4/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #3 on: October 16, 2018, 11:32:44 PM »
mmccarn, TerryF

Thanks for those answers & links.

Definitely not promising re using the Amaysim/Optus SIM as port 25 is likely to be blocked. I did ring Amaysim support who said no ports were blocked but it was apparent to me that they did not understand what I was talking about so I think their advice is unreliable.

I  have a home ADSL nearby with TPG, so I pulled a hard drive out of the sme server & built a duplicate server & installed that at home. Just had to change the login details in the sme console & change the external DNS to point my domain at the home static IP address. Mail was flowing almost immediately & changes have propagated overnight thru the Internet.

I redirected all user mails to local delivery plus forward to an external mail account.

I have been using phone tethering on a standalone PC in the office the last 2 days to get some limited Internet access & read mails on that external account.

I am thinking now to add that PC to the network via a router as an additional network (setup in server manager), running on a different LAN IP/subnet to suit the phone IP (which is totally different to our LAN IP).
With Internet Connection Sharing enabled in Windows, hopefully that phone Internet connection will be accessible across the network.

If that does not work then I can setup a 4G modem & integrate it to the LAN....or maybe just wait till Telstra fix the cut lines.

Never setup a router to add another network, so always a first time & a rapid learning curve !

Thanks
...

Offline ReetP

  • *
  • 3,722
  • +5/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #4 on: October 18, 2018, 12:51:15 PM »
There are some routers out there like the Drayteks that you can add a USB SIM stick and use it as failover so if your main ADSL goes off it will automatically use the SIM stick.

Your only real issue as mentioned is email, and that one is a real bind, hence I decided to host my mail server in the cloudy sky thing using SME on a virtual machine.

In hindsight that was one of my best decisions ever :-)
...
1. Read the Manual
2. Read the Wiki
3. Don't ask for support on Unsupported versions of software
4. I have a job, wife, and kids and do this in my spare time. If you want something fixed, please help.

Bugs are easier than you think: http://wiki.contribs.org/Bugzilla_Help

If you love SME and don't want to lose it, join in: http://wiki.contribs.org/Koozali_Foundation

Offline raem

  • *
  • 3,972
  • +4/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #5 on: October 24, 2018, 04:18:13 PM »
Dear All

Just to pass on the final workaround.
I purchased a 4G LTE modem & an Amaysim SIM card, configured it as firewall & gateway, then connected it to a spare port on the LAN hub.
I then reconfigured the server to server only mode & set Internet gateway IP as the modem IP.
Internet acess was then available to all workstations & for accessing the now remote sme mail server.

Still waiting for Telstra to repair the cut cable !
...

Offline ReetP

  • *
  • 3,722
  • +5/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #6 on: October 24, 2018, 04:32:19 PM »
Cool - it's pain when they don't bridge :-(

Glad you got it sorted, and clearly they pass Port 25 traffic which is good to know
...
1. Read the Manual
2. Read the Wiki
3. Don't ask for support on Unsupported versions of software
4. I have a job, wife, and kids and do this in my spare time. If you want something fixed, please help.

Bugs are easier than you think: http://wiki.contribs.org/Bugzilla_Help

If you love SME and don't want to lose it, join in: http://wiki.contribs.org/Koozali_Foundation

Offline janet

  • ****
  • 4,812
  • +0/-0
Re: sme9.2 alternative Internet access via 4G wireless modem
« Reply #7 on: October 25, 2018, 04:38:50 PM »
ooops
Please search before asking, an answer may already exist.
The Search & other links to useful information are at top of Forum.