Not so Dynamic Host Configuration Protocol

February 5th, 2016

Warning: Longish, network nerd content. Look away now if not interested.

DHCP. Wonderful thing, it is. You connect a device to a network, it automagically configures itself and starts working. We all use it (nearly) every time we turn on our laptop, tablet, smartphone, PC, or indeed Internet-connected fridge (FFS).

One company I do work for has started using Avaya IP phones- 1600-series ones, with an Avaya IP PBX, which will gradually replace a network of several over 10 year old Nortel PBXs. To make things easier, the phones will be configured with DHCP, a fairly well documented process.

The central site, with a larger network, has seperate VLANs for voice and data, with one DHCP server on the data VLAN. This is not a problem: the Cisco switches are configured with their interfaces having these two lines in:

switchport access vlan 20
switchport voice vlan 30

Which means untagged traffic will use vlan 20, and voice traffic needs be tagged with vlan 30. The DHCP to do this is easyish too;
in the normal DHCP scope that relates to the data vlan, we add an option 242, with the value

L2Q=1,L2QVLAN=30,VLANTEST=0

The phone will boot into the untagged data vlan 20, and read this option in the DHCP offer it receives. It will then know that it needs to tag it’s traffic with vlan 30, and request an address tagged with that. The router for the voice VLAN then has a

ip-helper [address of DHCP server]

statement to forward on the request. In the voice VLAN, we add option 242 again:

MCIPADD=[a.b.c.d],MCPORT=1719,HTTPSRVR=[a.b.c.d],VLANTEST=0

This actually tells the phone how to find the PBX.

This was all well and good, and indeed working well. Get a brand new phone out, plug it into a configured port, and away it goes.

But…

Smaller offices don’t have the seperate Voice VLAN; it just gets mixed in with the data traffic, and they need some of the new phones. No problem. In fact, this should be easy; we can dispense with all that tedious VLAN nonsense, so we can miss out the Cisco config above, miss out the second DHCP scope, and miss out the first instance of option 242, just adding an option 242 to the local DHCP like this:

MCIPADD=[a.b.c.d],MCPORT=1719,HTTPSRVR=[a.b.c.d]

Yes, it’s not the recommended config, but it is documented around the web, and the previous Nortel IP phones managed.

So, a colleague tries it, taking a working phone to a remote site where I’ve configured the server in just that way. The phone fails to boot. Static addressing fails too, with a odd “failed router” message. Trying to emulate the multiple VLAN setup fails too, and breaking out Wireshark (always the last resort, but the most wonderful tool for free) showed no DHCP requests reaching the server, and testing the server with a laptop works just fine.

Much head-scratching and a full day of testing and debate the next day reproduces the fault at the main site, and a bit more googling reveals that what the PBX engineer told us about not being able to reset the phones unless they register with a PBX is just wrong, though there’s many different suggestions of how to do it, depending on firmware. A reset to factory produces a phone requesting configuration in either the single-VLAN or dual-VLAN operation and booting correctly.

The problem here is that the phone here is very much misunderstanding the Dynamic part. It should, as all the devices I mentioned at the start do, check in with the DHCP server at each boot, and thereby cope with moving site or a network change. It doesn’t. It caches configuration data, trying to use it even when the network around it has changed substantially.

To me, this is just broken behaviour, and here’s the point of the post: if your Avaya 1608/1616 IP phone doesn’t seem to be taking any notice of your DHCP server, then “>the answer is here: from the linked blog:

Plug phone in.

When "* to program" shows press *.

When "enter PROCPSWD" shows enter C R A F T # on the keypad.

Press # to all the values shown and when "Enter command" shows (will be the last option) press the mute key and enter the following: C R A F T C L E A R #

"Clear all values?" will show. Press # and # again to confirm.

Taphouse 1: The Fountain, Walsall

January 31st, 2016

PubBlog Link
WhatPub Link
100Pubs Link

Given that The Fountain is an easy one to get to, and well loved by everyone on the 100 pubs tour, it was a ideal start for our taphouse adventure. It is, of course, currently the only pub owned by the Backyard Brewhouse, and serves their excellent beer, as well as a few guests.

The Fountain, taphouse 1 of n

The Fountain, taphouse 1 of n

It scored as Follows:

Ambience 8
Beer choice/quality 8.8
Architecture 6.8
Cobs/Pies/Snacks 9.6
Toilets 9

Which means an overall score of 8.44.

Taphouse Tour

January 31st, 2016

Following on from last year’s 100 Pubs adventure, we decided on a twist in our ways to drink too much contribute to the pub trade and have a bit of a giggle.

We’ve lowered the count this time, but added a challenge in other ways.

The challenge is Taphouses: that is, a brewery’s primary pub or bar. If the brewery is on site, all the better, but this isn’t always the case.

There’s ground rules.
1. The challenge is a minimum of 10 taphouses.
2. Each participant must drink at least 1 of the home brewery’s beer.
3. A photo of the taphouse must be taken.
4. Any 3 of the originators must be present, as a minimum.
5. Arrival (at least the last mile) should be by public transport, or walking (maybe cycle?)
6. Each taphouse will be scored out of 10 on ambience, beer choice and quality, architecture, pies/cobs/snacks, and toilets. Yes, Andy and me gave in on this one!

Each visit will be recorded here. If it’s a pub I’ve not been to before, it will get an entry on PubBlog too.

Scoring works as follows: each person judges in each category out of 10. The mean of the scores in each category is then published, and then the mean of those is taken (by summing them and dividing by 5) to give an overall score.

All your files are exactly where you left them

January 13th, 2016

The title of this post comes from a Windows message displayed during a update to Microsoft Windows 10. At the time @theardvaark posted this tweet voicing his distrust of the statement, I muttered to myself “Don’t be soft. Why on earth would a simple windows update move them?

Despite now having worked with the Evil Empire’s products for something like 27 years, and so being used to useless error messages (“An unexpected error has occurred”, for example) and being downright lied to (any message produced by Internet Explorer), I still get caught out at times, and one such thing gave me a nasty shock the other day.
Read the rest of this entry »

#100pubs2015: The Finale

December 31st, 2015

We did it.

The challenge set by Andy was completed last night, with some good company we hit pub number 100 at The Turf Tavern, aka Tinky’s, having already used the original choice of The OC’s very recently, we needed a reachable, nice pub for our final one, and, as it is happily now open again, this filled that role admirably.

We’re planning a new drink-related challenge for 2016- just a few things to check out first, and we’ll also be publishing our findings during the challenge at some point.

That Time of Year

December 21st, 2015

No, not the festive season. It’s the time of year again when I have to get the bike in the kitchen for cable replacements. It’s always this time of year, it seems. Christmas: ’tis the season to strip and replace gear and brake cables, so I took up the festive bike maintenance position in the kitchen, and this time didn’t lose any pingfuckits.

I had hoped my lower mileage this year might have avoided this, but obviously the last couple of runs to Chasewater in the mud (after which I hosed both the bike and myself) have made a mockery of that, with gear selection getting tricky and the brakes less effective. I’ve bought a different gear cable this time, with extended ferrules in places, so hopefully I might get a bit longer out of these.

#100pubs2015: The Home Straight

December 20th, 2015

Despite a hangover (from all of four pints, FFS) on Saturday, I managed to get my errands done in time to get out by bus and meet Andy in Walsall for the start of another push at 100pubs2015. The start was going to be what used to be The Pen and Wig, but it is now The Lounge, and was shut. We considered a diversion to Arbor Lights, but the beer didn’t inspire us, so off the The Wheatsheaf it was, as it fitted our route- Brimingham, via The Bartons Arms. After that, we did a few Birmingham City Centre pubs, which will appear on PubBlog if previously unvisited, and will appear over on Andy’s blog (link above) once he gets a chance to log them.

Usual target is 5 pubs per trip, so we were pleased to see off 7 in this trip, leaving us at 99 completed. Now we have to pick pub 100, and try to reassemble as many of our companions on some of the trips together as possible for a final episode between now and Dec 31.

Getting The Turtle’s Head

December 13th, 2015

Yesterday saw us at the Brownhills Christmas Market mid-morning, and having beer forced upon us by the nice chaps at Backyard. As reported over on BrowhillsBob’s Blog the event seemed a success, despite the weather, though I felt last year’s layout, with a cluster in Ravenscourt worked better, but given relations between Walsall MBC and the owners may be a little awkward, maybe co-operation on that front wasn’t possible, and it may also be that the chosen layout was deliberate to encourage foot traffic along the High St. Whatvever, we had a wander, the aforementioned beer, and caught the attention of a bird or two:

"Cats, you say? Nom."

“Cats, you say? Nom.”

then off to Aldridge, to order our turkey, and check out The Turtle’s Head, (snigger) Aldridge’s first Micropub, which made for a pleasant interlude, and all by public transport, which has to be better than staying sober and mucking about parking.

A kick up the 80s

November 22nd, 2015

We’ve been away, unshiunto Lanzarote. Winter sun, so while you lot were enjoying the dark, cold, wind, and rain, we were relaxing, drinking and eating. My usual irrational fear of a disaster of some type didn’t happen this time, and largely things were nicely uneventful, with the worst thing to happen that I managed to break my Kindle e-reader. Happily, between some dead-tree books obtained locally (it’s good to go somewhere frequented by English tourists) and my dear better half loaning her older kindle some of the time, I got sufficient reading material; I don’t read a great deal, apart from on holiday…

I did look at obtaining a new Kindle locally, but local gadget shops are famed for fakes and scams, and the packaging looked wrong, so I didn’t take the chance, having narrowly escaped a dodgy camera seller back in 2009. With new device purchased (hint: Amazon will offer a discount on a new one if you’ve broken your Kindle, even when it’s over 3 years old)

Anyway, the 80s thing? I have never heard so much 80s music in one place before; every bar was playing Internet/Sky radio stations, and the 80s soundtrack was constant. Odd. Is it the demographic?

Not So Swift

October 19th, 2015

I bought a Swiftcard, because it seemed like a great idea. I’ve been waiting for it to be valid on National Express West Midlands, simply because those are the buses I use the most, and finally, it is, so I bought two cards (one for my better half), and off we trotted (well, I hobbled) to get a bus.

The Pay As You Go card is simple; it replaces cash. You top it up with credit, allow auto top-up if you want, and then buy a ticket, but instead of hunting for change, you slap the car on the reader, and tell the driver what you want. They press the right keys, a ticket is issued, and the cost comes off your Swiftcard. Not before time, as most buses in our area do not give change, and the price of two all-day tickets means notes get involved unless you have close to 10 quid in coins, and notes get jammed in the coin chute.

So, the theory is Swiftcard fixes this.

I’ve now used the card three times. The first time, the driver just didn’t know what to do, so just let us on. The second time, attempting to buy 2 tickets, we were charged for one, and the driver thought the top-up receipt (top-ups happen automaticatally on buses, or you can use a terminal at bus stations, or an Android device with NFC and the app) was a second ticket. On the third occaision, the bus was quiet, so I explained how it is supposed to work to the driver, and he worked it out 🙂

Clearly, at least at National Express, no one has told the drivers, and I’m not alone.

Swift.

Swift.

The system’s great, and in my experience, the tech all works, but they really need to train the drivers, who I’m sure will be just as frustrated. It’s also interesting that just as we get our electronic cash-replacing card, London’s Oystercard gets phased out, replaced by contactless debit cards.


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