Synology Drive extremely slow!! omg, help needed.

Currently reading
Synology Drive extremely slow!! omg, help needed.

Yes, I am using Drive Backup. I am also using Drive Sync for a different reason.
Yes, same test files for each transfer.
I was getting file transfers via drag and drop(250-300 Mbps) with no issues 1 month ago, and then something has changed. I am sure it is a setup issue somewhere, but not sure what has changed between Windows and NAS. I plan to move to a different backup process as Drive has been a pain since I changed my PC.
Sorry to highjack this thread.
1. Check SMB setup (Win side), help from official MS KB:

2. then check NAS SMB3 settings in Control panel. You can use search in this forum (advisable)

3. for any reason and Win OS (baremetal or selected parts) backup purposes is Syno Active backup for business (AB4B in this forum) 10000x better than Syno Drive. You need change your thinking about right backup attitude.
Last edited:
Hey all,

This problem drives me crazy!

Just bought a DS1621+ on Raid 5. Installed it at home on my router.
I have a 1Gbps internet fiber connection at home.

I installed Synology Drive client on my home computer and my coworker's computer at his place also.
He also has a 1Gbps fiber internet connection at his place.

Here's the very simple setup:

View attachment 2567

We're trying to sync video projects, since we're into video editing. The other day it took 3 DAYS to sync 600GB of files for a project.
Upload speed of 2 to 3 Mb/s. Insanely slow. It should have take 4 to 6 hours max, not 3 days...

I used the Drive client using Quickconnect and DDNS, both are slow.
On my router I have ports 5000; 5001; 6690 and 80 forwarded and open.
The NAS is on its own dedicated IP, no DHCP.
Everything wired, no WiFi.

With dropbox using the same config, we use to have 30 to 60Mb/s transfer between dropbox and our computers and dropbox servers.
Now that I migrated all our data to the NAS, we're getting only 2 to 3Mb/s using the same configuration.
...on a 1Gbps connection, this is quite frustrating not being able to use the available bandwidth.

Between PC1 and the NAS I'm getting 80 to 120Mb/s. It's on the same router so that's okay.
But between the NAS and PC2... only 2Mb/s. On both DDNS or Quickconnect.

Did lots of test with my ISP, they swear the network works flawlessly at 1Gbps...

Any idea what is going on here? Is it Synology drive client app or network or config?

DS noob here,

I am having the exact problem, brand new DS1621+, 5 x 8TB, simple Nas-to-switch-to-computer, all 1GB, large or small files, no other traffic, never seen it get above 4MB per second using xcopy /j, robocopy, explorer, etc. VERY poor performance.

Ok on second look, I it's not the exact same problem as Dexxer, I'm not going through the cloud at all...
I have this level of performance INTERNALLY
mapped drive letter to NAS - not going outside my own LAN.

NOTE: the drives are still doing their parity check thing, 5th day = 80%
I know this hinders performance but 4MB / sec?
What should it be when this process is completed?

Thanks for any suggestions !
What should it be when this process is completed
If you are on a 1G lan connection, not more then 110MB/s +/-.

the drives are still doing their parity check thing, 5th day = 80%
This will have a huge impact. Best to wait for it all to complete.
My slow sync over internet is finally fixed!! :)

I called my ISP. For the fourth time. And finally a tech guy was honest enough to adjust somethings in my account that suddenly fixed the issue!

We're now syncing at 80-90Mb/s instead of the terrible 5Mb/s I had last month.

He did not mentioned what was changed... That is very strange. I have a feeling they were throttling the connection somehow. He probably changed my latency settings or something. Now, I really feel the 1Gbps internet I'm paying for! Finally.

I think ISP do some weird stuff to internet feed. Especially residential areas. Even tho speedtest shows 1Gbps it does not show the true pictures.

Thanks for the help y'all!

How did they make my Drive Sync client go from 5 to 90mb/s?? Without changing my internet plan?
Without changing my internet plan?
QoS probably (Quality of service throttling). They might have had some policy for specific ports/services and what speeds are allowed. As soon as he removed the policy (or apply a new one) it was fixed.
Last edited:
How did they make my Drive Sync client go from 5 to 90mb/s?? Without changing my internet plan?
My cable broadband router has a configuration view and I can see the bps that are set for in/out bound flows. I know it's bps even though it doesn't day this as the inbound matched my plan but for a long time the outbound hadn't changed from an older limit. It took until recently for them change this and push the new configuration, without reboot.

But it can also be a QoS on the types of traffic, of which Drive may have been classed as low priority. Unless you have a business plan you will probably be expected to want fast inbound and slow out (DNS, HTTP requests, etc are small size vs a streamed movie). But this now doesn't reflect people wanting to use their TB of cloud storage... how do they get data into these services if they are restricted to a few Mbps outbound?
I'm wondering if it's legal. They sold me on 1000mbps down and 750mbps up.

And they throttle the upload? This is shady business... 5Mb/s on a 1 Gbps connection is not fair. Now I'm happy. But I can't believe I had to call them 4 time and fight with them to get my advertised speed.

The 1st 3 times I called they asked me to do a bunch of speed test. All showing 1000/750 but in actual use of the NAS I never was able to reach those speed between the NAS and computers at home of office.

I guess you're right about QoS.
They probably "detect" server type use. Does that mean using a VPN would've fixed the issue also? Or they can still detect big upload even with a VPN?
Does that mean using a VPN would've fixed the issue also? Or they can still detect big upload even with a VPN?
VPN is a special eye-candy for some ISP providers. Some don't care for it, others don't allow it. Rest keep it under special QoS policies.

Also speed via VPN would be maybe the same in your case (until now). You should test it now that you know what your speed is. With VPN expect slower speeds (10-50% slower). If you get into those 5MB/s again, you can then be certain that you have hit another "policy" and will have to talk to them again.

If you get let's say 40-60MB/s then it's safe to say you are running on a solid VPN connection utilizing your current ISP speed (VPN encryption will add overhead so keep that in mind).
I’m glad you got it fixed. So most of our theories turned out to be incorrect :(
It must be something about throttling certain protocols as @Rusty said. That’s the most logical explanation to what happened I guess. I’m sure they won’t tell you (unless you know someone inside).

They might reset something (or apply a generic policy again) and you’ll be back to square one.
So take note of the date this got fixed, the name of the support person who fixed it (if you know it), any acronyms or buzzwords that they mentioned or mumbled (before you forget them) and if you have any support tickets that you can refer to in case you need to raise this again. Because you might need to go through a few “in-DUH-viduals” before you get to someone who knows the secret recipe (and believes it’s not illegal to think).
The above might save your time (and your sanity).

I'm wondering if it's legal. They sold me on 1000mbps down and 750mbps up.
I’m sure they’re protected. They can do it. It must be somewhere in a fine print in the service agreement you accepted/signed :)
I'm not an attorney of the ISPs, but:

1. It's their own infrastructure, shared with you
2. Mass market is out of any guarantees except of obligation to pay for the service provided
3. you can find this in your contract conditions

you have 5 possible choices:
1. Stay and pay for no SLA public product
2. Find some new ISP
3. Purchase Guaranteed SLA based Product = Pay more
4. Move to region with better services
5. Find a way how to share better infra via air or wire for few bucks (mentioned also here by me). There is also official way how to do it.

But people would like pay less for more, then we have such clash here. Seen anywhere and anytime.

Technical point of view:
- there is an owner of the main infrastructure. Many times here in EU it's diff. company from the ISP. Take it as wholesale.
- the owner of the infrastructure in EU must provide same conditions for all connected ISPs
- ISPs must pay for SLA, product and transferred data capacity
- then some of them (ISPs) have their own last mile infrastructure for data throttling (ofc, they pay for the capacity)
- and they have their own router connected to their own Management systems
- people like try to download a lot of trashes every day = then the infrastructure is exhausted = then is necessary to invest to new infra (backbone, regional, city, street, houses). It costs.
- but mass market customers like their "freedom" to move from one ISP to another "anytime"
- then the business in this area is tricky = you can tray it = open your own business as ISP.

Then it's possible that in same region you will purchase same infrastructure from diff. ISP. Take it into account. Otherwise you will purchase some sh.t!

I know something more about this business. I'm not ISP or affiliated. But I don't have a rose-colored glasses in this case.
When you need better NAS than your small box, you need also pay more for bigger one. There isn't vendor who will guarantee the max. speed of possible RAID transfer, ... No one. But people like white papers and take this as single source of truth.
And cheap is not always synonymous for a quality = cheap ISP router underperformed at 1Gbps Fiber line.

Hi I’m new around here. Nice to meet you all. I’m a bit of a clown when it comes to tech so this may not be what you are looking for at all. May be an entirely unrelated issue but just thought I’d pass this on just in case it helps. It’s saved me months of wasted upload time....

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Hello all,

I know this is an old thread but wanted to add one word here that may help you work with your ISP if they are willing. QoS generally will work by giving preference to specific packets when they are present and lowering the speed of other things as that traffic it in use.

The thing that a lot of ISPs use indeed is packetshaping, which is a way to sniff the packets and say that a specific type should use only a percentage of the total connection. So, this would allow you to go to a speedtest website and see your full speed but then go into an app and see a completely different result.

In my case I was able to ascertain they were using that on my link and urged them to stop and let me decide how to use the bandwidth they sold me, and it worked.

Hoping I can contribute here in the forum.

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Similar threads

You can add the new drive and change the RAID type to RAID1 (which is what SHR is in a 2 drive array).
It took a long time (months!) for me to figure out what was the bottleneck with stuttering/buffering. The...
Give an example? Also, use the locations as well. Are you running a BTRFS or EXT4 file system?
Hey! That’s not very SynoFormy of you 😡 Just kidding. Glad you found it 😃 Don‘t change this router for as...
Hi so I purchased a synology unit for company Backups. I have had it going and setup for a year without...
  • Question
I was going to do that last night and today but I have really bad cell reception where I live and couldn't...

Welcome to! is an unofficial Synology forum for NAS owners and enthusiasts.

Registration is free, easy and fast!