I’m having trouble uploading large files to S3. Smaller files work fine, but anything over a few hundred megabytes either times out or fails with errors. I need help figuring out the best way to upload large files reliably using the AWS S3 console or CLI. Any advice on optimal settings or troubleshooting steps would be appreciated.
Hurling Huge Files to S3 Without Losing Your Mind
So you’re staring down a mountain of files that need to get up to S3. Terabytes, maybe? Congratulations, your bandwidth is about to get a workout. There’s a right way and a very, very wrong way to do this—let’s keep you out of upload purgatory.
Rethink the “Just Drag and Drop” Approach
First mission: don’t upload everything at once unless you enjoy stalled .zip files and mysterious errors at 3AM. Trust me, that path leads straight to frustration and probably some corrupted files.
Chunk it up:
Break your data into digestible pieces. Think of this like sending a massive sandwich in bite-sized chunks, not as one overwhelming mouthful. Use the multi-part upload feature that S3 offers. This is basically splitting your upload into parallel streams, and it’s honestly a game-changer for speed and reliability.
Bandwidth Isn’t Unlimited, Even If You Wish It Was
Let’s talk speed bumps. Even if you pay top dollar for fast internet, home broadband’s no match for thousands of gigabytes. Weekends become “upload watch parties,” and nobody wants that.
- Prioritize uploads. Get the hot files up first.
- Schedule giant transfers when you’re less likely to be using the connection—think late night or early morning.
Permission Slips Matter
Before you blast off, double-check your AWS credentials and bucket permissions. Yeah, it’s basic, but you don’t want to find out hours later that your user doesn’t have access, or your bucket’s locking you out. Been there, done that, deeply regretted the lost time.
Tools or Bust: Don’t Just Use the Console
There’s only so much you can do through the AWS web UI before your nerves start to fray. GUI freezes, error pop-ups, and having to constantly babysit the browser window? No thanks.
I like to keep things streamlined, so I use dedicated software that lets me mount S3 as if it were another drive on my desktop. Options like CloudMounter let you treat cloud storage as if it’s a regular finder window. Makes dragging over files as painless as moving them from one folder to another.
Lifehack Checklist
- Turn on S3 versioning: So if you accidentally overwrite everything, you’re not toast.
- Monitor your costs: Massive uploads = bigger bills. Use AWS calculators or budget alerts.
- Encryption: Always a good idea. Client-side for sensitive stuff, or enable bucket-side encryption.
War Stories—Because Everyone Has One
There was this one time: I tried moving a full backup direct through the AWS console. Eight hours in, my browser crashed. All progress torched. Switched to a third-party app; I could pause, resume, and my connection drops didn’t mean starting from zero. Changed my upload life forever.
TL;DR
Large S3 uploads? Break the job into chunks, automate with the right tool, check your permissions and bandwidth, and never, ever trust a single, monstrous drag-and-drop. CloudMounter can make the whole ordeal feel like moving files locally—not like wrangling with the world’s worst courier service.
Good luck out there!
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Not gonna lie, big S3 uploads are a special kind of torture—reminds me of watching paint dry, except the paint randomly vanishes and your floor gets a mess. I saw @mikeappsreviewer’s detailed breakdown on chunking with multi-part and using helpers like CloudMounter (which is honestly solid if you just want something brain-dead simple for mounting S3 as a drive) and most of that’s gospel for reliable bulk uploads.
But here’s a leftfield take: command line tools are your underappreciated heroes. Forget GUIs (they crash, lag, and demand babysitting—agree). Try AWS CLI or even rclone for huge files. Real talk: with AWS CLI’s aws s3 cp --storage-class STANDARD_IA --recursive, you get resume-friendly uploads, can script retries, and never need to watch a spinning progress wheel. With rclone, you get throttling, robust retries, and logging, so you’ll actually know what died and why.
Honestly, network flakiness is inevitable with monster files. My trick? Set CLI tools to auto-retry. Example: aws s3 cp file.zip s3://my-bucket/ --expected-size 1048576000 --no-progress --cli-read-timeout 0 --cli-connect-timeout 0—zero timeouts, no more random fails. Also, don’t sleep on using EC2 if your upload is bottlenecked by local speeds—spin up a temporary instance in the same region and upload from there. You’ll go from hours to minutes, sometimes.
And, tbh, multi-part upload is NOT optional for files >100MB; it’s a must. But there’s a caveat: if you go the DIY script route, test the script with a small file first. Accidentally trashing a 10GB upload because of some hidden credential fail is soul-crushing, and S3 bills you for abandoned parts after 7 days. You didn’t want to pay five bucks to store junk, trust me.
So, to sum: skip the drag-n-drop, try something like CloudMounter for “it just works” vibes or CLI/rclone if you want control. And, unlike @mikeappsreviewer, I actually like using the AWS Console to verify the final state—it’s slow, but sometimes old-school visuals are the only way to sleep at night.
Maybe overkill, but at least you don’t have to rage-refresh at 3AM.
Not gonna lie, uploading big files to S3 is basically an ancient rite of digital frustration. @mikeappsreviewer and @sterrenkijker both nailed the essentials: if you’re still trying to push a 2GB file through the AWS Console, you’re braver (or more foolish) than most. Multi-part uploads and CLI tools are your new best friends, period.
But here’s the twist nobody’s talking about—network infrastructure & local bottlenecks. I’ve seen folks try every tool under the sun, then realize their home router is throttling packets like it’s still 2009. Before you blame S3, check your gear. And yes, WiFi is not your friend here. Go wired, or your mega-upload is going to drop every time someone fires up Netflix in the next room.
Honestly, everyone harps on automation and CLI, but sometimes you need a “set-and-forget” solution. CloudMounter is decent for this, especially if you want a Finder/Explorer workflow, but (unpopular opinion) nothing beats a small EC2 instance in the same region as your bucket. Upload your files to EC2, then push to S3 internally; you’ll be drinking coffee while 10GB moves in five minutes. Those upload failures will become ancient history.
Also, random tip: avoid simultaneous uploads if you’re on a shaky connection—sometimes serializing them is actually faster and keeps AWS happy. Oh, and clean up abandoned multi-part uploads with aws s3api list-multipart-uploads and then abort as needed. Those orphaned chunks = wasted money.
tl;dr: stop using the console, check your local network, go CloudMounter for drag/drop, or script it with CLI/rclone. If you’re desperate for speed and reliability, go the EC2 route and marvel at what “in the cloud” really means. And yeah, can confirm: losing a whole upload at 99% is how technology breaks people.
Yeah, multi-part upload is a must, but let’s zoom out—‘bandwidth’ isn’t just about your ISP. If your home gear or WiFi is ancient, you’re throttling performance at the first hop. (Agreed with earlier points: go wired or give up weekends to failed uploads.) Now for the juicy bit: CloudMounter shines if you’re a drag-and-drop devotee, making S3 feel like ‘just another drive’ (big plus for less technical folks or anyone scarred by AWS CLI syntax). Bonus: Supports other clouds if you bounce between services. BUT—and this is where some will disagree—it’s not for power-users needing logging, scripting, or low-level AWS integration. Reliability? Solid, unless your connection hiccups mid-transfer; there’s sometimes less feedback about failures compared to CLI tools. Cost? You’re paying for GUI convenience. Competitors like those using scripts or the official AWS CLI (as mentioned by the others) give you granular control and automation if you can handle the learning curve.
So: For simplicity and Finder-style uploads, CloudMounter is top-shelf. Just know you’re trading advanced scripting for UI comfort. Pair it with a decent wired network and maybe keep an eye on abandoned multi-part uploads in the AWS dashboard for best results.