Net - macOS

  • app failing with no route to host
    Settings → Privacy & Security → Local Network → then allow xxx
netstat -nat
netstat -i
networksetup -listallnetworkservices
networksetup -getdnsservers <service>
networksetup -getsearchdomains <service>

mtr <host>

# List DNS config
export services=$(networksetup -listallnetworkservices | tail -n +2)
echo $services |while IFS= read -r service; do echo $service ; networksetup -getdnsservers $service; done;
  • netstat
  • ifconfig
  • ndp
  • arp
  • route
  • networksetup

route -n get xx
ip r get xx
man networksetup

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

# firewall
/usr/libexec/ApplicationFirewall/socketfilterfw


# troubleshooting
nslookup google.com
dig google.com
host google.com

nslookup google.com 8.8.8.8
dig @8.8.8.8 google.com

scutil --dns
networksetup -getdnsservers Wi-Fi
networksetup -getdnsservers "USB 10/100/1000 LAN"  # adjust interface name

networksetup -listallnetworkservices

dig +trace google.com

dig -x 8.8.8.8
nslookup 8.8.8.8

dig google.com MX     # Mail records
dig google.com NS     # Name servers
dig google.com TXT    # Text records
dig google.com AAAA   # IPv6 records

cat /etc/resolv.conf

sudo dscacheutil -cachedump -entries host

sudo dscacheutil -flushcache
sudo killall -HUP mDNSResponder

sudo tcpdump -i any port 53

telnet 8.8.8.8 53
nc -u 8.8.8.8 53  # UDP test


scutil --dns | grep -A 5 "resolver #"

sudo brew services list
sudo brew services stop dnsmasq
  • MacOs networks
    ip -4 a |egrep -v 'DOWN|link|utun[0-9]'
  • https://github.com/brona/iproute2mac — See list of tools there
    • netstat, ifconfig, ndp, arp, route, networksetup
    route get xx
    man networksetup
    
    sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
    
    # ip ported to macos
    iproute2mac
    Homepage: https://github.com/brona/iproute2mac
    This is CLI wrapper for basic network utilities on Mac OS X inspired with iproute2 on Linux systems.
    Provided functionality is limited and command output is not fully compatible with iproute2.
    For advanced usage use netstat, ifconfig, ndp, arp, route  and networksetup directly.