MacOS name had (#) and increasing

I noticed last week that my computer name was (2). I have done the macOS updates when they come out. There have not been any other system changes or additions. This morning I see that my computer name is now (3). This is effecting my DNS resolution being that it changes from systemname to systemname-3. I am not changing the name of my system. Why would this have occurred? After the last update I did notice that my NIC has stated there was a duplicate NIC on the network. I only use the NIC through the CalDigital Dock. Cisco 3750x-48P-S switch is running c3750e-universalk9-mz.152-4.E10.bin since 2020 with no problems.


Also in Tag you question, Select your device its also showing systemname(3). I am not changing the system name and very concerning.


MBP

2.4 GHz 8-Core Intel Core i9

AMD Radeon Pro 5500M 4 GB

Intel UHD Graphics 630 1536 MB

32 GB 2667 MHz DDR4

16"



MacBook Pro 16″, macOS 13.5

Posted on Sep 14, 2023 7:08 AM

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4 replies

Sep 14, 2023 7:16 AM in response to MauWoW

This is an annoying issue that's been present in macOS for a while now where the Mac will see it's own Bonjour discovery attempts and get confused. The most common cause of this is having both WiFi and Ethernet enabled at the same time.


You might want to either use the IP address of your machine to identify it, or set up a fixed DNS record on your network or on the other machine to point a device name to the IP of your computer.

Sep 15, 2023 9:07 PM in response to MauWoW

And what IP address does your laptop have? Is it the static IP or is it grabbing a dynamic IP? Just because you configured something a certain way does not mean that each device is still configured that way, so you need to double check everything on the router, dock, and laptop regarding network related settings. You may want to check the router's logs to see if this laptop was connected with different IP addresses since that would at least confirm the problem and help you determine what needs to be adjusted.

Sep 18, 2023 7:09 AM in response to HWTech

Everything on this VLAN is static assigned with no DHCP. I have other VLANs for local LAN and Wireless that transverse a Cisco Router. The router has relay agents on the sub-interfaces to my Windows Server 2022 Active Directory Server also doing DNS and DHCP for these network. The devices have reservations inside DHCP. Untrusted Wireless is going through Cisco ASA. Cisco WLC 5508 is providing DHCP for this VLAN but after initial devices are added they also get a reservation DHCP address. There are no logs on any of the Cisco equipment related to Layer 3 changes. DHCP is only used for new devices that I add just to L3 connectivity then moved to specific range in the VLAN. Only 3 addresses are active per VLAN and do not communicate with anything until I make a firewall change for http, https or ssh. Even if DHCP would have taken over I would have had more problems.


Noticed PRTG server shows communication loss to the MBP DNS name from around the time I noticed the system name being changed randomly. IP Address was still showing active. The error went away after changing the system name again. Actually was ignoring the PRTG server errors thinking it was something to do with the VCF environment I was creating.


The problem is Red Hat OpenShift Container Platform relies solely on DNS. In this VLAN / LAB, communication stopped with the YAML Server and the environment inside the MBP. The Application Firewall did not like that he name and IP Address did not match but after changing the name back everything was worked.


Over all it is the MBP changing the system hostname that is causing the problem. Saturday evening the name changed on its own again saying a new interface was detected. Nothing was added and DNS resolution stopped. After a reboot I was able to change the name back and continue. Not sure why this is happening now. Seem since a couple updates back it started to occur.


Would there be something in iCloud that would be causing the problem? Couple updates ago iCloud process started to hang. Having to kill it and then run "killall bird" to sync again. It was fixed before sometime back but happening again. Just a thought.

MacOS name had (#) and increasing

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