Packet Capture - Cisco vs Juniper

Cisco 
monitor capture fileName interface portNumber both 
monitor capture fileName match any
monitor capture fileName buffer size 10
monitor capture fileName start
monitor capture fileName stop
 
***export to flash: or bootflash:***
monitor capture fileName export location flash:fileName.pcap
 
Juniper
Monitor traffic interface <interface> extensive write-file /var/tmp/<file-name>
CTRL + C to stop the capture
Monitor traffic interface <int> write-out /var/tmp/name.pcap

Debug DHCP issues

Setup pcap filter, then bounce port to restart DORA process
monitor traffic interface irb.503 no-resolve detail matching "udp port 67" count 150 write-file dgw_VLAN_650_DHCP_11-17-21.pcap
 
DHCP client traceoptions
set system processes dhcp-service traceoptions file <filename>
set system processes dhcp-service traceoptions file size 20m
set system processes dhcp-service traceoptions file files 10
set system processes dhcp-service traceoptions level all
set system processes dhcp-service traceoptions flag all
monitor start  filename.tr
monitor stop filename.tr