$ curl cheat.sh/
 cheat.sheets:iftop 
# iftop
# Display bandwidth usage on an interface by host.

# Display bandwidth usage on the default interface
iftop

# Display bandwidth usage on a specified interface
iftop -i eth0

# Show or hide DNS hostnames
iftop -n  # Show network traffic without resolving hostnames

# Limit the display to IPV4 or IPV6 traffic
iftop -4  # Show only IPV4 traffic
iftop -6  # Show only IPV6 traffic

# Set the screen update interval to 5 seconds
iftop -t  # Use text interface
iftop -s 5

# Display bandwidth in bits instead of bytes
iftop -b

# Adjust the sort order of hosts
iftop -o source  # Sort by source address
iftop -o destination  # Sort by destination address
iftop -o both  # Sort by both

# Display cumulative usage since start
iftop -c

# Use a custom filter code, e.g., to monitor specific port traffic
iftop -f "port 80"  # Show only HTTP traffic

# Show only a specific number of lines
iftop -N 10  # Display the first 10 lines only

# Freeze the current display to observe
iftop -F

These are some common use cases for using `iftop` to display bandwidth usage by host on a network interface.

 tldr:iftop 
# iftop
# Show bandwidth usage on an interface by host.
# More information: <https://manned.org/iftop>.

# Show the bandwidth usage:
sudo iftop

# Show the bandwidth usage of a given interface:
sudo iftop -i interface

# Show the bandwidth usage with port information:
sudo iftop -P

# Do not show bar graphs of traffic:
sudo iftop -b

# Do not look up hostnames:
sudo iftop -n

# Get help about interactive commands:
?

$
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