When trying to install Nvidia Sync and it asks for my spark login info, I get: [image] I am able to ssh to the spark and use the web ui after creating a tunnel. Any suggestions on how to remedy this? Brian Andrus

I found that starting Nvidia Sync from a command prompt made it allow the entries. Odd. Now it works as expected.

One of the fixes suggested in previous posts was to use the IP instead of hostname. See NVIDIA Sync fails to add new host with error "Invalid Argument Host already exists"

Yep. I have been using IP address and getting the message.

When Host already exists error pops-up the easy way to fix it is to delete or edit Host in /home/$USER/.config/NVIDIA/Sync/config/ssh_config I had this configuration: elsaco@huston:~/.config/NVIDIA/Sync/config$ cat ssh_config Host spark Hostname spark User elsaco Port 22 IdentityFile “/home/…

Do you have a match condition in your ssh config? NVIDIA Sync fails to add new host with error "Invalid Argument Host already exists" - #5 by sio2boss

Hi, please reference our FAQ for how to resolve this issue [image] DGX Spark / GB10 FAQ DGX Spark / GB10 Initial Setup <a name="p-1694056-q-i-am-trying-to-set-up-my-dgx-spark-in-appliance-mode-i-am-able-to-connect-to-the-dgx-spark-ssid-but-it-cant-open-the-webpage-it-tries-to-redirect-me-to-httpspark-xxxxlocalhttpspark-xxxxlocal-2" class="anchor" href="#p-1694056-q-i-am-trying-to-set-up-my-dgx-spark-in-appliance-mode-i-am-able-to-connect-to-the-dgx-spark-ssid-but-it-cant-open-the-webpage-it-tries-to-redirect-me-to-httpspark-xxxxlocalhttpspark-xxxxlocal-2"> Q: I am trying to set up my DGX Spark in appliance mode. I am able to connect to the DGX Spark SSID, but it can’t open the webpage it tries to…

This fixed. I had a match condition for something called platform.sh and removing the entry fixed it for me

Nvidia Sync gives "Invalid Arguement" when trying to add Spark

Accelerated Computing DGX Spark / GB10 User Forum DGX Spark / GB10

aniculescu October 28, 2025, 4:21pm 7

Hi, please reference our FAQ for how to resolve this issue

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Nvidia Sync gives "Invalid Arguement" when trying to add Spark

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