AssetCacheLocatorUtil(8) System Manager's Manual AssetCacheLocatorUtil(8)
AssetCacheLocatorUtil – Utility for reporting information about macOS
AssetCacheLocatorUtil reports information related to macOS Content Caches
running on the computer or on the local network.
Some of the information that AssetCacheLocatorUtil reports depends on the
current network configuration, and on the user running it. It might
produce different results for different users, on different client devices,
or on different networks. Applications that use content caches might
choose ones other than the ones AssetCacheLocatorUtil reports due to
factors beyond its knowledge, such as iCloud affinity.
AssetCacheLocatorUtil reports the following information separately for
system daemons and for the current user:
The system can temporarily save a hint about whether or not there
might be content caches on the computer or on the local network.
AssetCacheLocatorUtil prints that saved hint if it is available.
Saved content caches
The system can temporarily save information about content caches it
has previously found on the computer or on the local network.
AssetCacheLocatorUtil prints that saved information if it is
Refreshed content caches
AssetCacheLocatorUtil forces the system to search for content
caches on the computer and on the local network and to refresh the
saved information above. It then prints the results.
Saved and refreshed public IP address ranges
If your network administrator has configured public IP address
ranges in DNS, which the system uses when looking up content
caches, AssetCacheLocatorUtil prints saved and refreshed
information about those ranges.
Saved and refreshed favored server ranges
If your network administrator has configured favored server ranges
in DNS, which the system uses when looking up content caches,
AssetCacheLocatorUtil prints saved and refreshed information about
AssetCacheLocatorUtil then reports the reachability status of all of the
content caches it found. If the computer cannot communicate with a content
cache over the local network then it cannot request files from that content
cache. However, just because the computer can "ping" a content cache does
not imply that that content cache will serve requests sent from this
The --json option prints the results in machine-parseable JSON format to
AssetCacheLocatorUtil also reports warnings about potential issues it
The Apple cloud service with which content caches register limits the
number of content caches on a network. This limit can change at any time.
If a larger number of content caches are available on a network than the
cloud allows, client devices might not always choose the "best" content
cache. AssetCacheLocatorUtil warns when it detects this possibility. The
number of content caches available on a network can be reduced by changing
the settings of some of the content caches, using System Preferences >
Sharing > Content Caching > press the option key > Advanced Options... >
Clients > Cache content for:.
AssetCacheLocatorUtil warns when it detects content caches with different
ranks. The exact value and meaning of each rank is defined by the Apple
cloud service with which content caches register, and can change at any
time, but client devices use only the content caches with the lowest-
numbered rank available to them. A content cache's rank can be changed by
adjusting its settings, using System Preferences > Sharing > Content
Caching > press the option key > Advanced Options... > Clients > Cache
content for:. A content cache on the same computer as the client always
has the lowest-numbered rank.
Having content caches in different ranks can be intentional or accidental,
depending on your organization. AssetCacheLocatorUtil warns about mixed
ranks in case it is accidental. An example of an intentional use of mixed
ranks is when a school has a content cache that caches content for devices
using the same local networks and the school's district office has another
content cache that caches content for devices using the same public IP
address. Client devices in the school use the school's content cache.
Client devices in a different school in the same district use the
district's content cache.
Every content cache must have a unique GUID. AssetCacheLocatorUtil warns
when it finds content caches in your organization with duplicate GUIDs. A
content cache's GUID can be changed by stopping the content cache, running
the following command in Terminal as an admin user, and then restarting it:
sudo -u _assetcache defaults write
/Library/Preferences/com.apple.AssetCache.plist ServerGUID = `uuidgen`
When public IP address ranges are configured but the client device's public
IP address is not in the configured ranges, this could prevent the device
from using your organization's content caches. AssetCacheLocatorUtil warns
about this condition. To configure custom public IP address ranges use
System Preferences > Sharing > Content Caching > press the option key >
Advanced Options... > Clients > My local networks: and set DNS TXT records
Your network administrator can designate some content caches as "favored."
AssetCacheLocatorUtil warns when it finds content caches that are not
favored, with the exception of a content cache on the same computer as the
client. Client devices use only favored content caches when any are
The system can temporarily mark content caches as "unhealthy" after
attempts to use a content cache fail due to either HTTP error responses or
network errors. Each client device maintains its own health records for
each content cache. Client devices use only healthy content caches.
AssetCacheLocatorUtil warns when any of the content caches it finds are
unhealthy. Note that when AssetCacheLocatorUtil refreshes the list of
content caches, it also resets the health of every content cache it finds
System Preferences > Sharing > Content Caching, AssetCacheManagerUtil(8)
macOS 8/1/19 macOS