我正在使用 Apple 的 CloudKit 技术开发 macOS 应用程序，并收到一位特定用户的错误报告，由于“网络不可用”错误，他无法与 Apple 的 iCloud 服务器同步数据。我很确定这是他的网络配置问题，因为我在 iCloud 日志文件中看不到他的客户端的任何内容，而且这种情况只发生在这个特定用户身上。我们想追踪问题，并已尝试了以下步骤：
- 用户安装了 LittleSnitch 并暂时关闭了网络过滤器，没有任何变化
用户无法 ping 通 Apple 的 CloudKit 服务器：
ping -c4 p61-ckdatabase.icloud.com:443 ping: cannot resolve p61-ckdatabase.icloud.com:443: Unknown hostApple Notes（也使用 CloudKit）中的同步功能正常
- 当他将 Mac 连接到 iPhone 热点时，问题仍然存在
启动应用程序时，系统日志中会出现以下消息：
problem 15:10:44.020090 +0200 cfprefsd attempt to write to a container /var/root/Library/Group Containers/7T8DYS43CJ.de.lisczyk.felix.SnipNotes that does not yet exist. Using client-provided container path without resolving symlinks.
fehler 15:10:44.020238 +0200 SnipNotes Failed to read values in CFPrefsPlistSource<0x6180000fe580> (Domain: 7T8DYS43CJ.de.lisczyk.felix.SnipNotes, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null)): Using kCFPreferencesAnyUser with a container is only allowed for System Containers, detaching from cfprefsd
standard 15:10:44.321589 +0200 SnipNotes [Crashlytics] Version 3.8.4 (121)
standard 15:10:44.436198 +0200 SnipNotes Faulting in NSHTTPCookieStorage singleton
standard 15:10:44.436230 +0200 SnipNotes Faulting in CFHTTPCookieStorage singleton
standard 15:10:44.436253 +0200 SnipNotes Creating default cookie storage with default identifier
standard 15:10:44.475833 +0200 SnipNotes 0x61000046e100 opened /var/folders/2r/_94bykls11dbzf_71qwcc47r0000gp/C/de.lisczyk.felix.SnipNotesMacApp//mds/mdsObject.db: 4636 bytes
standard 15:10:44.476194 +0200 SnipNotes 0x61800046ba00 opened /var/folders/2r/_94bykls11dbzf_71qwcc47r0000gp/C/de.lisczyk.felix.SnipNotesMacApp//mds/mdsDirectory.db: 50744 bytes
standard 15:10:44.477688 +0200 SnipNotes 0x61000046e100 opened /var/folders/2r/_94bykls11dbzf_71qwcc47r0000gp/C/de.lisczyk.felix.SnipNotesMacApp//mds/mdsDirectory.db: 50744 bytes
standard 15:10:44.479548 +0200 SnipNotes 0x608000c60180 opened /Users/user/Library/Keychains/login.keychain-db: 344032 bytes
standard 15:10:44.483240 +0200 SnipNotes 0x608000c60500 opened /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates: 25604 bytes
standard 15:10:44.485988 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.486137 +0200 SnipNotes 0x600001874e00 opened /Users/user/Library/Keychains/Microsoft_Entity_Certificates: 31108 bytes
standard 15:10:44.489005 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.489110 +0200 SnipNotes 0x61000046f5c0 opened /Library/Keychains/System.keychain: 163852 bytes
standard 15:10:44.491864 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.491965 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.492204 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.492360 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.492548 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.492670 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.492879 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.492983 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.493224 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.493317 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.493628 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.493755 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.493995 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.494104 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.494338 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.494438 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.494674 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.494801 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.495032 +0200 SnipNotes TIC TCP Conn Start [1:0x618000381110]
standard 15:10:44.495793 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.495933 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.496195 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.496298 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.496605 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.496723 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.497016 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.497146 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.497395 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.497530 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.497785 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.497880 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.498038 +0200 SnipNotes TIC TCP Conn Start [2:0x60800019e6b0]
standard 15:10:44.679542 +0200 SnipNotes TIC TCP Conn Event [1:0x618000381110]: 1 Err(0)
standard 15:10:44.679567 +0200 SnipNotes TIC TCP Conn Connected [1:0x618000381110]: Err(0)
standard 15:10:44.679687 +0200 SnipNotes TIC Enabling TLS [1:0x618000381110]
standard 15:10:44.680485 +0200 SnipNotes TIC TCP Conn Event [2:0x60800019e6b0]: 1 Err(0)
standard 15:10:44.680510 +0200 SnipNotes TIC TCP Conn Connected [2:0x60800019e6b0]: Err(0)
standard 15:10:44.680690 +0200 SnipNotes TIC Enabling TLS [2:0x60800019e6b0]
standard 15:10:44.825914 +0200 SnipNotes TIC TLS Event [1:0x618000381110]: 2, Pending(0)
standard 15:10:44.829242 +0200 SnipNotes TIC TLS Event [1:0x618000381110]: 11, Pending(0)
standard 15:10:44.830154 +0200 SnipNotes TIC TLS Event [1:0x618000381110]: 12, Pending(0)
standard 15:10:44.830214 +0200 SnipNotes TIC TLS Event [1:0x618000381110]: 14, Pending(0)
standard 15:10:44.831864 +0200 SnipNotes TIC TLS Event [2:0x60800019e6b0]: 2, Pending(0)
standard 15:10:44.834275 +0200 SnipNotes TIC TLS Trust Result [1:0x618000381110]: 0
standard 15:10:44.834397 +0200 SnipNotes TIC TLS Event [2:0x60800019e6b0]: 11, Pending(0)
standard 15:10:44.837836 +0200 SnipNotes TIC TLS Event [2:0x60800019e6b0]: 12, Pending(0)
standard 15:10:44.837882 +0200 SnipNotes TIC TLS Event [2:0x60800019e6b0]: 14, Pending(0)
standard 15:10:44.842192 +0200 SnipNotes TIC TLS Trust Result [2:0x60800019e6b0]: 0
standard 15:10:44.959226 +0200 SnipNotes TIC TLS Event [1:0x618000381110]: 20, Pending(0)
standard 15:10:44.959586 +0200 SnipNotes TIC TCP Conn Event [1:0x618000381110]: 8 Err(0)
standard 15:10:44.959619 +0200 SnipNotes TIC TLS Handshake Complete [1:0x618000381110]
standard 15:10:44.960159 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.960309 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.960739 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.960976 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.961243 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.961423 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.961683 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.961795 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.962831 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.962977 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.963267 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.963430 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.963751 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.963947 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.964021 +0200 SnipNotes TIC TLS Event [2:0x60800019e6b0]: 20, Pending(0)
standard 15:10:44.964297 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.964330 +0200 SnipNotes TIC TCP Conn Event [2:0x60800019e6b0]: 8 Err(0)
standard 15:10:44.964356 +0200 SnipNotes TIC TLS Handshake Complete [2:0x60800019e6b0]
standard 15:10:44.964496 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.964794 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.964914 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.965168 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.965316 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.965767 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.965969 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.966246 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.966379 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.966724 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.966888 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.967214 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.967405 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.967743 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.967853 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:44.968149 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Intermediate_Certificates
standard 15:10:44.968322 +0200 SnipNotes skipping upgrade for locked keychain /Users/user/Library/Keychains/Microsoft_Entity_Certificates
standard 15:10:45.130344 +0200 SnipNotes TIC TCP Conn Cancel [1:0x618000381110]
standard 15:10:46.587492 +0200 SnipNotes Helper Performance: Please update this scripting addition to supply a value for ThreadSafe for each event handler: "/Library/ScriptingAdditions/SIMBL.osax"
如果您能就如何隔离问题提供任何建议，我将不胜感激。谢谢！