Power Cuts & Battery Backup

[ITGURU]

Does anyone know to what extent, beyond a schools site, that there is battery backup in place at exchanges/4g masks etc.

In the event of a town power failure, would a BT leased line still be accessible via phone exchange battery backup?

When the Advant fibre interfaces are installed they are installed with UPS so they remain online, but just wondered how much internally is any use on an UPS even if its not accessible remotely in the event of a power outage. i know they are there to cover short blips or short power cuts, but if a remote sites local area had a power outage if id still be able to gain short access in,

Alternatively, i am wondering if i had a 4g router installed in the server room that if there was a power outage, 4G networks would still be available?

What are people;s thoughts or understanding in terms of battery backup of Internet services?

[SchoolsBroadband]

@ITGURU that is a very good question.

 

I've just been trawling through BT Openreach documentation to try and find the answer but I can't.

 

As standard BT Openreach offer resilient UPS which are physically located in a cabinet which a Communications Provider (CP) equipment is located in. They also offer SLA's associated to this UPS and power feeding those UPS's too. However I can't find what backup power they actually have within exchanges as standard. Ive been to a few in the past and i've seen some with diesel generators and multiple power supplies.

 

Major exchanges are likely to have these but I'm unsure of smaller more rural ones. Certainly all do have UPS as a minimum.

 

If you want me to send you BT Openreachs co-mingling product (you need to be a CP to have access to this but I'll happily send you a copy i've got this evening) which explains what they offer to CP's then I'll happily show you this which gives nice pictures and a description of eveything.

 

My view is that you're more likely to have resilient power which last for longer at an exchange than at a cell site. Cell sites do go down quite a bit although they always have battery backup. I'm unsure how long they as standard last for.

 

Remember quite often 4G can actually go back via the telephone exchange depending on how close you are to it. These networks do try to self heal though in the event of a cell site outage.

 

if you want the best i'd generally say get one BT based leased line and one from a completely different carrier (e.g. Cityfibre or Virgin) and ask the different carrier if the line would go via the local BT telephone exchange (this does sometime happen!).

 

More than happy to give any more advice if the above is helpful.

 

Dave

[ITGURU]

If you don't mind then that would be great. please PM me. 2 sites I work at have different broadband providers but both have a BT 21CN adva media converter at the sites so it's after this point it makes me wonder if there is any backup power in place at the other end of the fibre. I assumed that all leased lines would still go back to the local exchanges..

[SchoolsBroadband]

Hi again @ITGURU

 

all leased lines using a BT EAD or BT EAD LA do go back to the local telephone exchange unless a specific RAO2 resilient variant has been used (highly unlikely as these are pricey).

 

It'd be pretty criminal of the LLU provider not to have a UPS in their rack in the telephone exchange but in theory this could happen. You'd need to ask the LLU provider.

 

I'll send over the document to you later on.

 

Thanks

 

Dave

[Fazza]

A battery backup like a UPS isn't really there to power the equipment during a power failure. In the event of a power cut it's main purpose is to either provide enough power for a graceful shutdown of the equipment so it doesnt get damaged or to provide enough time for a backup power solution to kick in like a generator for example. I would expect a BT exchange to have a generator for when power-cuts occur??

[SchoolsBroadband]

I think most do I just can't find the documentation on the Openreach website at the moment As soon as I do I'll pass it on

[Fazza]

I think most do I just can't find the documentation on the Openreach website at the moment As soon as I do I'll pass it on

 

It wouldnt surprise me if this was 'top secret' or confidential information that BT doesnt give out as I did 1 weeks work placement with BT (a few years back now) when I was in the 6th Form and even just for that I had to sign the official secrets act so I could go inside a BT exchange.

[ITGURU]

A battery backup like a UPS isn't really there to power the equipment during a power failure. In the event of a power cut it's main purpose is to either provide enough power for a graceful shutdown of the equipment so it doesnt get damaged or to provide enough time for a backup power solution to kick in like a generator for example. I would expect a BT exchange to have a generator for when power-cuts occur??

 

Hi

I understand that the UPS is there for a graceful shutdown. However when you have remote sites that have power loss for extended times, whereby the battery backup also loses power, what's there to signal all systems to start up again once power is restored as if its a graceful shutdown it would need a physical press of a button to start the servers up again?

[jmak]

Hi

I understand that the UPS is there for a graceful shutdown. However when you have remote sites that have power loss for extended times, whereby the battery backup also loses power, what's there to signal all systems to start up again once power is restored as if its a graceful shutdown it would need a physical press of a button to start the servers up again?

There's often a setting in BIOS which you can set to turn on the server when power is restored. Most of the UPSs will wait until they are fully recharged before they supply power to their outlets - we once had a faulty one that got stuck in a cycle of restarting every time the power came back on and then promptly sitting down as it detected that there wasn't enough power in the battery.

 

https://www.apc.com/us/en/faqs/FA158943/

[Fazza]

Hi

I understand that the UPS is there for a graceful shutdown. However when you have remote sites that have power loss for extended times, whereby the battery backup also loses power, what's there to signal all systems to start up again once power is restored as if its a graceful shutdown it would need a physical press of a button to start the servers up again?

 

In the scenario of a device being only on a UPS with no generator and a graceful shutdown is performed, a person must physically go and power back up the server for example.

 

A generator is required if you wish to have no loss of service in a major power failure.

 

 

There is normally a setting in the BIOS to power a machine back on in the event of it not being gracefully shutdown so when the power returns, it powers up but if it's been gracefully shutdown I dont know how a BIOS would know the difference between a human running a shutdown command and a piece of software running the same shutdown command for example.

 

 

Virgin Media for example have portable generators that can go in the back of one of their vans and move around to some of their equipment in the street should a power failure occur (i.e. construction worker digging through one of their power cables) that they can use until the issue has been resolved.

[CCCSecMan]

Surely if the local telephone exchange lost power then your site would probably be affected too - so at that point bit pointless having a 4g backup. Unless your site has a backup generator or something..

 

You would generally need resilient fibre links which travel in opposite directions and go through different POPs. For a school or educational establishment this seems a bit overkill?