Are rewritable CDs/DVDs less reliable than CD-R / DVD-+R?

[mikeymikec]

Looking through my wallet of OS setup / memory test CDs/DVDs (and the fact that there must be at least 4 Win10 discs in there), it seems silly in hindsight that I didn't use rewritables.

 

[mxnerd]

Rewritable - 25 years. Write once - 200 years, only in theory.

DVD is so bad that even a bit of body oil can prevent the disc being read correctly.

Stopped using optical discs over 10 years.

Using ISO file exclusively now for OS setup. Write the setup ISO to USB drive when needed.

 

[mikeymikec]

Interesting, I've never had any trouble (or at least if I ever had a single incident of a recordable becoming unreadable, I don't remember) with re/writeable discs. I keep the ISO files for all the valuable ones anyway, and I'm aware that the tech behind re/writable discs has somewhat more issues with longevity than a physically printed disc.

I guess given that I keep ISO backups, the idea that a rewriteable could fail me at some point is not a big deal, but I would be interested in knowing more about whether rewriteables are more problematic than writables.

- edit - when you say "DVD is so bad", I assume you mean DVD recordables in general (rewritable and DVD-+R)?

 

[mxnerd]

- edit - when you say "DVD is so bad", I assume you mean DVD recordables in general (rewritable and DVD-+R)?

Yep. But maybe I'm very careless about them.

 

[VirtualLarry]

Use quality media and a decent drive to burn them (PI and PO scans on DVDs on a good "scanner drive" can help here. Is CDRInfo or CDFreaks still around?), and they'll last quite a while.

I wouldn't recommend re-writeables. They are FAR less reliable, IMHO. You've done good by using DVD-R/+R discs. Besides, they cost what, $0.10 to maybe $0.25 (USD) ea.? Pennies a day. Plus, they burn way faster (16x versus 4x) than re-writables, and the cost savings of re-using a re-writable gets eaten by the time cost spent burning them slower, and spending time erasing and verifying them. Plus, the cheaper ones don't last for more than 10-12 re-writes successfully. That's one reason why the UDF filesystem for DVD+-RW was invented, to work around defective sectors, and allow to keep using the disc. Which of course, doesn't help if you're burning bootable ISO images to disc.

 

[dlerious]

I've been writing to optical for a long time, starting with CD-r then DVD-r and now MDisc Blu-ray. I create images using IMGBurn leaving enough room for ECC data. I use dvdisaster to compute and add the ECC to the image (RS02). I'll have to grab some older disks and see how they've held up - last time I checked 15 year old disks were still readable.

 

[mikeymikec]

Sod's law dropped by yesterday to give me a slap.

I went to install Lubuntu (on another machine) using the same disc as I successfully used on my own machine a few months ago (DVD+RW), and the machine immediately and completely refused to even acknowledge that a disc was in the drive, while reading DVD-Rs fine.

Now that I come to think of it, rewritables were sometimes a problem with some drives

My reason for wanting to use rewritables - it seems silly to burn an OS image to a disc, for it to have maybe 3 years of potentially useful life, and then be chucked out rather than re-used. I'm not a fan of helping to fill landfills.

Brand: I tend to stick with TDK, they've worked well for me.

 

[VirtualLarry]

My reason for wanting to use rewritables - it seems silly to burn an OS image to a disc, for it to have maybe 3 years of potentially useful life, and then be chucked out rather than re-used. I'm not a fan of helping to fill landfills.

My attitude? Honestly, it's saving ME time, MORE reliable than -RW, and F-it, they're cheap enough.

 

[Borealis7]

you can get X13.6 times (64 / 4.7) more space on flash drives than DVDs for around 15$, why bother?

 

[Insert_Nickname]

I've had good and bad experiences with rewritables. Generally, they're pretty reliable, as long as you stick to quality media and don't rewrite them too often.

Also, storage. Keep cool and out of sunlight.

As for longevity, that'll require a significant post all on its own.

I'll have to grab some older disks and see how they've held up - last time I checked 15 year old disks were still readable.

I've got some CDs I wrote in the late 90's. 20 years and they're still perfectly readable today. I check them once in a while to see if read errors crop up. So far, so good.

you can get X13.6 times (64 / 4.7) more space on flash drives than DVDs for around 15$, why bother?

Because flash drives are also unreliable. If you just need an install media, no issue. But I wouldn't trust them for archiving. Oh, and BDXL media go all the way to 128GB, and are cheaper then flashdrives on a per GB basis.

 

[lxskllr]

Optical media's the floppy drive of this time. I'll do everything I can to avoid using it. I much prefer usb drives.

 

[Thebobo]

I have some old CD RWs that shouldn't works but still do. Back from the Napster days.

 

[mikeymikec]

you can get X13.6 times (64 / 4.7) more space on flash drives than DVDs for around 15$, why bother?

It's been trivially easy to write an ISO to a CD or DVD regardless of the platform, but I don't know how to write an ISO to a flash drive. I'm using Lubuntu these days, and I'd like to learn how to.

Having said that, I'd need to buy about 10 flash drives and store them (they don't exactly stack/tidy away easily), and I suspect DVDs are still somewhat cheaper.

 

[mxnerd]

I have experienced all sorts of odd things about using optical discs.

One of them was that sometimes you could burn a disc on brand A's optical drive,

yet It won't read the disc it just burnt. The disc could be read by brand B's drive, however.

 

[mxnerd]

I don't know how to write an ISO to a flash drive

Most popular utility is Rufus.

https://rufus.ie/en_IE.html

Used YUMI for multiboot, but it does't always work. It's kind of try and error.

https://www.pendrivelinux.com/yumi-multiboot-usb-creator/

==

You can also use MicroSD memory card with a reader if you have them laying around, you don't have to use flash drives.

 

[bononos]

Use quality media and a decent drive to burn them (PI and PO scans on DVDs on a good "scanner drive" can help here. Is CDRInfo or CDFreaks still around?), and they'll last quite a while.
.......

Cdfreaks changed to Myce to sound more 'professional'. The problem with quality media is that there aren't any around anymore. All the old good brands are just cashing in on their name and selling relabeled Ritek or CMC.

 

[Insert_Nickname]

I have experienced all sorts of odd things about using optical discs.

One of them was that sometimes you could burn a disc on brand A's optical drive,

yet It won't read the disc it just burnt. The disc could be read by brand B's drive, however.

Ah, classic.

Usually caused by media quality and too high burn speed.

Cdfreaks changed to Myce to sound more 'professional'. The problem with quality media is that there aren't any around anymore. All the old good brands are just cashing in on their name and selling relabeled Ritek or CMC.

Ever since Taiyo Yuden pulled out, you just cant get high quality media anymore. Not that it matters much today, since optical discs have mostly been relegated to archival duties*, like tape drives.

Good thing USB drives took of like they did. They're far more flexible.

*Where you want phase change media like bluray (of the non-LTH variety) or M-Disc.

 

[dlerious]

Cdfreaks changed to Myce to sound more 'professional'. The problem with quality media is that there aren't any around anymore. All the old good brands are just cashing in on their name and selling relabeled Ritek or CMC.

I haven't bought new in a while. Used to use Taiyo Yuden CD and DVD with a few Kodak CDr. What do you use now to check the manufacturer? My Mdisc have been pretty good, but I don't think I've ever verified who made them.

 

[LTC8K6]

It's been trivially easy to write an ISO to a CD or DVD regardless of the platform, but I don't know how to write an ISO to a flash drive. I'm using Lubuntu these days, and I'd like to learn how to.

Having said that, I'd need to buy about 10 flash drives and store them (they don't exactly stack/tidy away easily), and I suspect DVDs are still somewhat cheaper.

They are getting pretty cheap, even for name brand USB3:
https://www.amazon.com/PNY-Turbo-128GB-Flash-Drive/dp/B00FE2N1WS

 

[lxskllr]

It's been trivially easy to write an ISO to a CD or DVD regardless of the platform, but I don't know how to write an ISO to a flash drive. I'm using Lubuntu these days, and I'd like to learn how to.

Having said that, I'd need to buy about 10 flash drives and store them (they don't exactly stack/tidy away easily), and I suspect DVDs are still somewhat cheaper.

dd if=filename.iso of=/dev/usbdevice

Make sure you get your target right. dd isn't known as DataDestroyer for nothing ;^)

 

[mikeymikec]

dd if=filename.iso of=/dev/usbdevice

Make sure you get your target right. dd isn't known as DataDestroyer for nothing ;^)

If you wrote a ~4GB ISO to a 32GB drive, wouldn't you need to do something to clean up the fs for the rest of the drive? Or would you start by formatting the drive with the fs that the ISO ends up writing?

 

[BSim500]

you can get X13.6 times (64 / 4.7) more space on flash drives than DVDs for around 15$, why bother?

Unpowered data retention, ie, you can hardly trust any flash based storage with stuff like sticking irreplaceable wedding photo's onto disk, placing it in the back of a cupboard for 10 years and expecting to read it after a decade of being unpowered. What works for being regularly plugged in doesn't work the same way for "cold storage" / archival. You might still be unlucky and get a bad disc you can't read, you will probably get good read-backs with a decent archival grade media (eg, M-Disc or inorganic HTL BD-R). But most flash drives especially the newest ones using the smallest 15-16nm TLC nodes have nowhere near the amount of overhead vs charge loss that early SLC / MLC +25-40nm based flash did and a lot of people have been burned with data loss. JEDEC specs for SSD's guarantee it for 1 year. That's not long at all for archival lifespan requirements.

As for "Are rewritable CDs/DVDs less reliable than CD-R / DVD-+R?" that depends on the media. The general rule of thumb is inorganic (phase-change) reflective layers are more stable vs degradation than organic (dye based) layers. Most CD-R, DVD-R and BD-R LTH are dye based. BD-R HTL and M-DISC (inc DVD MDISC) are phase change based. It's certainly possible for a RW to last longer than dye based R discs. In fact DVD-RAM (the one that came in cartridges) were rugged as hell and rated for 100k cycles (vs 1k for DVD+/-RW):-
http://blog.digistor.com/not-all-blu-ray-discs-are-created-equal-but-does-bd-r-quality-matter/

Whether optical is worth it or not depends on cost and capacity. If you have a very large video collection (say 8TB worth), you're probably better off buying and mirroring extra 8TB HDD's than burning an impractical number of 1,700x DVD-R's or 320x BD-R's. OTOH, if you have a small amount of critical data (say 100GB), then a pack of 10x BD-R's that allow you to burn 2x copies of each 23GB x5 disc works out cheaper than the cost of 2x 128GB USB sticks yet still remains viable for user time / number of discs burned.

Golden rule of backing up - Don't make a backup, make 2-3, so comparing 1x 128GB flash drive / SSD with x equivalent amount of discs is false as if you value your data for achival purposes, you'll be making more than 1x backup regardless of medium, and needing multiple flash drives regardless of capacity. And if the data trickles out of flash drives at 10-40% per year, whilst HDD's magnetic field degrades at 1-2% and optical doesn't at all, you could make 100x backup copies on 100x flash drives and after 10 years, end up with 100x very blank "backups" where even the file system and partition have vanished from charge loss whilst that CD you burned on ye olde Mitsumi 1x speed drive on your 486 back in 1993 is still readable today.

 

[Insert_Nickname]

In fact DVD-RAM (the one that came in cartridges) were rugged as hell and rated for 100k cycles (vs 1k for DVD+/-RW):-
http://blog.digistor.com/not-all-blu-ray-discs-are-created-equal-but-does-bd-r-quality-matter/

I can attest DVD-RAM is rugged as hell. Before blu-rays they were the go-to media for archiving critical* video data. Data retention should be at least 30 years.

Further, they have the additional advantage for more common data, that they work like a regular HDD for data access. No burning software required, just format with FAT32 or UDF and you're good to go. Data is stored in concentric tracks, unlike the spiral track normally associated with optical media. ECC is also hardware based, and baked in.

*Critical as in very important. I'll leave the rest up to imagination.

 

[shortylickens]

I havent burned a disc in many, MANY years.

Why is this even a question?

 

[Oyeve]

I recently went through a MASSIVE apartment cleanout and came across a few 10-packs of COMPUSA branded DVD 1X discs that are at least 15 years old. And they still worked. Then I found a box of a few 100 piece spindles of Rimage discs still sealed. Man, every time Newegg had a sale I bought a few hundred. I haven't burned a disc in years and really see no need to as I can by bulk usb flash drives for way less than the price on one single CDR back in 1998. Blanks were like 50 buck each back then.