Why does the system start swapping when I try to dump core using the request system core-dumps command?
The show system core-dumps command displays a list of system core files created when the device has failed. This command can be useful for diagnostic purposes. Each list item includes the file permissions, number of links, owner, group, size, modification date, path, and filename. You can use the core-filename option and the core-file-info, brief, and detail options to display more information about the specified core-dump files.
You can use the request system core-dumps command to perform a non-fatal core-dump without aborting the routing protocol process. To do this, the routing protocol process is forked, generating a second copy, and then aborted. This process can double the memory consumed by the two copies of the routing protocol processes, pushing the system into swap.
For more information, see Junos OS Routing Protocols Library for Routing Devices