Why did this window pop up in High Sierra?

[blackxacto]

17,1 iMac, macOS 10.13.4
So I opened up a pdf in a pdf reader, and this window pops open. Why am I being prompted about the name on my iMac in the system? Why does it have something to do with sharing?

 

[fisherking]

you have more than one mac; they both have the same name, and the os (not just HS) will rename one to keep their identities seperate, as they're on the same network. standard behavior..

 

[blackxacto]

I have ONE iMac, ONE iPad Pro (10.5”), ONE iPhone SE. Where is it seeing the second Mac?

 

[Bornee35]

on your network

 

[fisherking]

did you previously have another imac? also, the network may just have seen your imac with a different IP address, and it's confused (seriously). it's nothing to worry about...

 

[blackxacto]

did you previously have another imac? also, the network may just have seen your imac with a different IP address, and it's confused (seriously). it's nothing to worry about...

I had another iMac two years ago. But what prompted this pop up?

 

[treekram]

Given what you've stated, maybe multiple network interfaces (Ethernet, Wi-Fi, etc.) are activated?

There's an article on troubleshooting here:
https://www.macissues.com/2015/05/18/fix-your-macs-network-name-getting-2-appended-to-it/

If you don't have any other Mac's on your network, you can skip #1 on the list.

 

[crjackson2134]

I had another iMac two years ago. But what prompted this pop up?

Network Connection (Same Network, Same Name (even if it is a ghost))

 

[blackxacto]

Given what you've stated, maybe multiple network interfaces (Ethernet, Wi-Fi, etc.) are activated?
There's an article on troubleshooting here:
https://www.macissues.com/2015/05/18/fix-your-macs-network-name-getting-2-appended-to-it/
If you don't have any other Mac's on your network, you can skip #1 on the list.

Thank you for the link. I tried to run the bonjour shut off command in terminal, but High Sierra does not recognize a command listed for Bonjour on/off. Does anyone have a link to a recent explanation on how to effectively rechange the Mac network name?

 

[iapplelove]

This issue was pretty popular years ago. My Mac got all the way up to MBP(3). Only had one mbp my entire life , th same one I’ve been using since 2012.

Not sure what causes it, but haven’t heard of anyone having this issue of renaming in a very long time.

 

[treekram]

It looks like discoveryd had replaced mDNSResponder but then it came back and mDNSResponder got retired.

I didn't realize Apple has made so many changes along the way on this aspect of the OS - usually this kind of stuff remains relatively stable.
https://help.dreamhost.com/hc/en-us/articles/214981288-Flushing-your-DNS-cache-in-Mac-OS-X-and-Linux

 

[blackxacto]

I have done a complete clean install of my 17,1 iMac. NO MIGRATION. I did drag my user documents folder back, but not a lot else. A lot of issues have gone away.