"Transfer the rails to the new drive unit. Make sure they are properly secured, by fastening as many of the screws you still have after losing a few under the false floor".
Wow. 340MB. Today, we'd be hard pressed to get anything done. My first computer only had a 52MB HDD. I had to replace it 5-6 times until a new system came along.
I did 5 E translations for cellular office testing at Bell South in Atlanta. Easy peasy. We were still using DAT tapes in 1996. Worked for Att bell labs, later Lucent 1996-2003. We were doing FOA (first office application) testing.
Which Lucent location(s) were you? I had an NJ-ALL badge in 99-01. If you were in any of my locations, there's a good chance I fixed your computer before. :-D
@@eric_d the last few years I was in technical support working with bell labs, resolving very difficult problems. I covered pretty much the entire Northeast of the country. I have a total of 36 years service, I started out, with Western Electric, in, February 1963. I work primarily with simple office electronic switching systems, 1 ESS, tsps, ETS, 4 ESS, 5 ESS, then technical support for all central office systems, throughout the entire Northeast.
@@americanspirit8932 I was only at Lucent about 2 and a half years, from 99 to 2001. My company was contracted to do all hardware support while IBMGS was supposed to handle all software support. I was on the refresh team (replacing computers at the end of their lease and transferring all the users files to the new computer), and the "break-fix" team (fixing any broken hardware). IBMGS totally screwed us over, and made us lose the contract, which put our entire company of over 7000 people out of business. During my time there I worked in at least 2 dozen different sites around New Jersey, from Mount Olive, to Princeton, to Red Bank, to Murray Hill, and everywhere in between.
Management: "There's no need for two people. This procedure should take at most ten minutes. You should have got the drive warmed up before, i'm slashing two hours off your pay."
Let’s see, 340 MB divided by 70 pounds... this drive gives you almost 4.86 megabytes per pound of disk! Show me a flash drive that can do THAT. Interestingly, despite the complexity, iFixIt still considers this a “Moderate” difficulty procedure.
Those synths 😍. In the nineties I once helped change a hard drive (in what one would now call a makespace) of about 1 kg per megabyte 🤣. It weighed over 70kg, requiring about three nerds with nerd carrying capacity 🤷♂️.
In the bell system, all memory was totally duplicated, with memory control is controlling, controlling all the data in a central office. If there were problems it's the one system would automatically switch, to the opposite memory which is totally duplicated, without skipping a Beat. Many audits run continuously through the Bell System, any discrepancies would kick out an alarm remove the suspect memory, and put the standby memory online that will run Diagnostics automatically, to see whether there was a memory error or a hardware error. The systems were totally bulletproof from access from outside sources, hash thumbs or monitored 24/7, with all the various audits running continuously 24/7. 100% foolproof from any, interference from anywhere in the world would be detected instantaneously, some of these comments show me that these people really didn't have an understanding how these systems really operate. I am a bit old school from number four and number five ESS, but I understood the operating systems completely, they were 100% foolproof, outside of a earthquake or building collapsing. Today is September 9th 2022.
This is still done nowadays but often at a higher level. Companies with only a few servers can put redundant drives in the same server (which is called RAID), but companies with many servers make the whole servers redundant, and don't bother putting redundant parts in each server.
It's amazing by today's standards how much effort Bell put into automatic testing and diagnostics though. Nowadays we don't bother to diagnose anything in detail.
@@thewhitefalcon8539 you have absolutely no idea what you're talkin about. The belt system is totally redundant, routine Diagnostics run, generally out-of-hours. These systems you cannot learn any college or university. We done the seat is because, communication is the first line of defense. They do not depend on individual privately-owned service doesn't work that way. Too complex and difficult to explain with a few words, what's the information is proprietary, to begin with.
If, like me, you were wondering what Bellcore was: it's effectively a mini Bell Labs Co started in 1983 for the baby bells, hence they were able to keep using the bell logo.
@@DoctorWhom: I wasn't trying to state whether he was right or wrong, duh. Try rereading my reply because you totally blew it. But I wasn't even talking to you anyway, so you really don't even need to worry about it.
We had had hard disk drives for 3 decades by this time, and they were already called hard disk drives or hard drives for a long time. Why did these guys think they still had to call them this weird name?
Yep, just pull and replace the SATA drive. If RAID, re-stripe. (depending on how big the CO is) -- I run my company's entire phone system on a thin client and a USB SATA dock (so I can make backups just by inserting a blank 128GB SSD and pressing the 'Backup' button) :)
Copyright 1989. 340MB, that's a huge drive for that era! "The unit weighs approximately 70 pounds." Ah, there you go. I wonder how much one of these spare drives cost.
do you think these older digital switches (DMS, ESS, etc.) will ever find their way to telephony/communications museums given their complexity and since many components for them no longer exist
Given that Verizon is buying parts on ebay to keep their switches running in addition to retiring copper at many Fios-enabled COs to increase their spare parts cache for the rest..... good luck finding spares. Verizon also seems to be determined to get all DMS-100s off their network due to Nortel going EOL and nobody supporting it. I suspect the 5ESS will be around for a while since there is still support from Alcatel-Nokia. The trend has been to consolidate their local switches to a regional Gentech C20 soft switch (which is replacing the older CS2000 switches).
Many of those switches are still in use today. And no, parts are no longer made for them. (your only hope is to find functional "spares" from out-of-service units.)
They will. A friend of mine acquired a DMS-100 for less than $2000 from a university last year and saved all of the cabinets except for some of the line card cabinets (don't really need more than a few for a museum/lab install) specifically for this reason. He aims to set up a museum around it one day... hasn't fully worked out powering it up yet, though. Needs quite a lot of amps of -48VDC...
@@kreuner11 yes, but the 3ESS is a monolithic system compared to the 5E. the challenges are far greater in regard to generic software images and operating a 1B computer -- huge electric bill. The best that can be hoped for is a 5ESS VCDX , I doubt we'll see a full fledged 5E unless Nokia or Bell Labs launches an effort to preserve software for historical purposes.
Fascinating. I understand switches like these are still operating to this day. So, do these units that are still operating have to be re-capped and retrofitted with modern storage devices? Also, I wonder what is actually stored on these hard drives.
They replaced 9 track reel to reel systems with these beasties. And I would not be surprised if they had set up storage systems with one adapter on top of another to enable semi-modern storage methods to be used. 5ESS systems are on their way out and very few are left, only in operation in fringe locations.
If they weren't still operating to this day, then what would've replace them, supposedly (besides maybe just smaller versions of the same thing that may run on a different OS, like System Signalling #7, etc.)?
I don't have my 5ESS manual handy at the moment, but I suspect that the storage was redundant, yeah. Not sure if it was RAID, like we use today, but almost certainly was something similar.
Worked on 5ess for a number of years. 5ess used hardware redundancy to increase reliability. The switch was required to be down for only about 2 minutes per year. As I remember, the disk file controller wrote the same data to 2 separate drives And ping pong reads from each drive, so it is similar if not equal to raid on a modern PC.
@@dalezapple2493 I'm a DMS guy, myself. NT went to "Disk-On-Pack" in 2002 and the lower capacity DOP daughter cards wrote to a larger disk for redundancy. You had to 're-image' a DOP if replaced. Do you recall when WECO/ATT went solid-state?
@@NortelGeek nope, in my time 5ess used the 300mb removable disks, and later 340mb non removable disk platters. For the 300mb the platters were about 15 inch diameter and 12 or so platters.
I thought for a second the size of the drive was 340 GB, about the same size as a drive that comes with a laptop. Nope, it's 340 MB. Times have changed.
@Miss Kobayashi I just listened to it again. It sounds more like the event printer which was probably impact type. Since they are servicing a drive, there's no doubt that it's throwing errors. It could just be papers being rustled, but it sounded like mechanical outpulsing the first time I listened to it.
I'd like to have seen them find a CDC drive which looked like it had been drop kicked out of the truck. haha I saw that at ATT's Beaudry Building in DTLA.
Why did they even bother with that number 3 sticker. Did they film an actual replacement? Quality with a capital K. We all know that sticker will be on the bottom of the cabinet tomorrow
It depends. Backbones are completely digital and a single 4 rack unit machine like an Oracle Acme Packet 6350 (which given its capabilities + licensing + redundancy might end up costing a million $ per pair, or more) can handle 3 million subscribers and 160,000 concurrent calls. Access networks are a little different as it depends what technology you get your phone service with. If you plug your landline to the back of your modem, it's digital as well and most likely connects to one of the aforementioned machines. If you have good old copper lines, also called POTS, it probably still looks similar to this video
@@icovada Yep, still a ton of 5E and DMS100 offices out there (And maybe a few XB5 and CG0) but they can't beat the offerings of an IP connection when it comes to price or variety. (Maybe in reliability, but that's a discussion for another time.) It's still fun to see these in action again, though. :)
"Are we still switching calls"? As opposed to what other supposed way of connecting one phone to another (even cell phone calls are switched in some way)?
@@HelloKittyFanMan. Sure but that's packet switching at layer 3 in the ISO/OSI pile, while the voice would be at layer 7. Either way, "switching calls" in my head is more of a circuit-switching thing, which definitely isn't happening anymore except for the last pure landlines at the last mile
I wonder if that drive was MFM, SCSI, or IDE? In the OG or Operations Gateway of the GTD-5, they were originally IDE mechanical drives, which were later upgraded to SSD Drives. The hard drives in the IROC of the GTD-5, which controls direct-interface to MXU/PairGain Cabinets, are still SCSI.
They aren't computer drives, first off. So no to IDE or SCSI. Just as computer drives were once proprietary to their interfaces (like ST506 for PCs), these were probably made just for ESS use.
- unmount the disk controller - turn off the disk - turn off the other disks - turn off the power to the disks - turn off the power to the disk controller - turn off the power to the disks again Aiyiyi...
