Short takes: calculating file transfer times; Internet breakout from cloud datacentres; and creating a VPN with a Synology NAS

Another collection of “not-quite-whole-blog-posts”…

File transfer time calculations

There are many bandwidth/file transfer time calculators out there on the ‘net but I found this one particularly easy to work with when trying to assess the likely time to sync some data recently…

Internet breakout from IaaS

Anyone thinking of using an Azure IaaS environment for Internet breakout (actually not such a bad idea if you have no on-site presence, though be ready to pay for egress data) just be aware that because the IP address is in Holland (or Ireland, or wherever) location-aware websites will present themselves accordingly.

One of my customers was recently caught out when Google defaulted to Dutch after they moved their client Internet traffic over to Azure in the West Europe region… just one to remember to flag up in design discussions.

Creating a VPN with a Synology NAS

I’ve been getting increasingly worried about the data I have on a plethora of USB hard disks of varying capacities and wanted to put it in one place, then sync/archive as appropriate to the cloud. To try and overcome this, I bought a NAS (and there are only really two vendors to consider – QNAP or Synology).  The nice thing is that my Synology DS916+ NAS can also operate many of the network services I currently run on my Raspberry Pi and a few I’ve never got around to setting up – like a VPN endpoint for access to my home network.

So, last night, I finally set up a VPN, following Scott Hanselman’s (@shanselman) article on Setting up a VPN and Remote Desktop back into your home. Scott’s article includes client advice for iPhone and Windows 8.1 (which also worked for me on Windows 10) and the whole process only took a few minutes.

The only point where I needed to differ from Scott’s article was the router configuration (the article is based on a Linksys router and I have a PlusNet Hub One, which I believe is a rebadged BT Home Hub). L2TP is not a pre-defined application to allow access, so I needed to create a new application (I called it L2TP) with UDP ports 500, 1701 and 4500 before I could allow access to my NAS on these ports.

Creating an L2TP application in the PlusNet Hub One router firewall

Port forwarding to L2TP in the PlusNet Hub One router firewall

Reconfiguring a Plusnet ADSL router (Sagemcom 2704n)

I’ve been trying to improve my Skype call quality at home and the guys I work with who know about this sort of stuff have suggested that my cheap ISP-supplied router may be part of the problem. Put simply, the Technicolor TG582n that Plusnet shipped me last year is fine for a bit of web surfing, it even streams video from iPlayer, etc. OK, but it’s not up to the task for P2P or real time media.

I was playing around with some of the settings and found that the router wasn’t behaving reliably (when I applied changes, and they weren’t applying) so I called PlusNet, who gave me two options: factory reset and a new router. I went for both.

The factory reset got me back up and running until the new router arrived. Plusnet’s current “Hub Zero” router is a Sagemcom 2704n and, whilst I’ve yet to see if my Skype for Business call quality improves, everything else about it seems to be a retrograde step:

The hardware design is flawed – when fixed to the wall, the router’s Ethernet ports are inaccessible (there isn’t enough room for them to turn through 90 degrees!) and, despite having a Gigabit Ethernet switch the ports are only 10/100 (yes, the ADSL connection is much slower than that but the cheap Ethernet ports reduce the speed of the local network).

Then, there’s the firmware that Plusnet have applied to the router which takes dumbing down to a new level. At least with the TG582n I could make a telnet connection for advanced configuration; Plusnet have blocked telnet, SSH and SNMP so there’s no way to manage the device. They’ve also removed the ability for ICMP to be enabled so my broadband ping trace flat-lined when I plugged in the new router:

PlusNet router blocks ICMP
No ICMP, no ping test

Worst of all, the Plusnet firmware hides the ability to change the IP address of the router, or to turn off DHCP. Given that I have a business account and that the paperwork with the router says “Welcome to Plusnet Business”, I’d have thought that almost any business with more than a handful of users would have its own DHCP server and may want to control the IP range in use (as I do – my Raspberry Pi does runs the infrastructure here). Luckily, after some hunting around I found a forum post with the details I needed:

Log into it using http://192.168.1.254/expert_user.html with the admin name and password.
Select >Advanced Setup >LAN
First select the ‘Disable DHCP Server’ radio button, then at the top, change the IP address

[…]

now click Apply/Save at the bottom. The 2704n will now update and the page will start to refresh but won’t complete as you now have to change the address in your browser URL bar to http://[yourchosenIP]/expert_user.html

In all likelihood, I’ll be buying a new router. Something decent for ADSL2+ that will also work if I do upgrade to FTTC later. In the meantime, at least I’ve managed to get over the biggest hump with reconfiguring the Sagemcom 2704n.

Reconfiguring a PlusNet ADSL router (Technicolor TG582n)

This post is probably not much interest to many people but it might help some if, like me, you’re trying to re-configure a Technicolor TG582n ADSL router from Plusnet. Just make sure you read all the way to the end and save yourself some time!

For the last 11 years, my ADSL connection has been running with an elderly Solwise SAR110 ADSL modem/router, provided by Plusnet when we first connected to 512Mbps ADSL. Those were the days – half a meg download speeds seemed so fast back then! Whilst fibre has (just about) reached my neck of the woods, my ADSL 2 connection is working well, most of the time, and I get about 6Mbps down and 0.7Mbps up these days. Indeed, the connection actually seems to have become more responsive lately (my theory is that the contention rate has dropped in line with people switching to fibre)!  I did have cause to call Plusnet for support last week though, and they agreed to ship me a new router if I signed up to one of their current packages (which, incidentally saved me money too as we were still on a very old tariff).

The new router is a Technicolor TG582n and I finally got around to setting it up tonight. I was told that I might get slightly faster speeds but there’s no evidence of that based on the tests I’ve run so far (that may change in a couple of days when we roll into a new billing month and onto the new service) [Update: after a few reboots my speed has doubled to around 12Mbps]. For now though I just want to swap the old router out for the new one.

The first thing I found was that the default configuration sets the router’s IP address to 192.168.1.254. That’s the IP address of my wireless access point, and all of my devices are expecting a gateway address of 192.168.1.1.  So, I downloaded the router configuration (Technicolor Gateway -> Configuration -> Save or Restore Configuration).  This gave me a file called user.ini, which I then searched for all instances of 254 and looked like they were part of an IP address (ignoring one which was part of a long string of numbers) and replaced 254 with 1.  I then uploaded the new configuration and, hey presto, the browser refreshed giving me back the config for my wireless access point on 192.168.1.254 and the router was responding on 192.168.1.1.  That seems a bit of a kludge and there should be another way to do this, but I couldn’t find it in the GUI (at least not with software release 10.2.2.B).

Then, reading around I found that the router also has a DHCP server enabled by default. I don’t want that right now (my Raspberry Pi is doing that job for me) so I started to investigate switching that feature off. Again, I couldn’t find it in the GUI, so I tracked down a copy of the CLI guide for the router (from another ISP – Demon – albeit for an older release) and, sure enough, after telnetting onto the box the dhcp server config command told me it was enabled so I corrected that with the following commands:

dhcp server config state=disabled
saveall

After all that, I found the config that I needed – it seems that the location to make the changes is Home Network -> Interfaces -> Local Network -> Configure.

There I found some handy checkboxes to turn on/off DHCP servers (IPv4 and IPv6) as well as the static address for IPv4 addresses!

After all this, I may well switch over to one of the popular open source firmware packages on the router… but I’ll leave it alone for now…