ntop upgrade fails because of rrd path not found, rrdtool is where you expect it to be installed

[TheLastLovemark]

Please forgive the terse descriptions, a little frustrated by now. I can only imagine how you all feel, dealing with this everyday.

Error message displayed after trying to build ntop

configure: error: Unable to find RRD at /opt/local: please use --with-rrd-home=DIR
Command failed:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_ntop/ntop/work/ntop-5.0.1" && /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_ntop/ntop/work/ntop-5.0.1/autogen.sh --prefix=/opt/local --with-rrd-home=/opt/local --without-ssl 
Exit code: 1
Error: Failed to configure ntop, consult /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_ntop/ntop/work/ntop-5.0.1/config.log
Error: Failed to configure ntop: configure failure: command execution failed
DEBUG: Error code: NONE
DEBUG: Backtrace: configure failure: command execution failed
    while executing
"$procedure $targetname"
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_net_ntop/ntop/main.log for details.
DEBUG: invalid command name "::ui_init"
    while executing
"::ui_init $priority $prefix $channels($priority) {*}$args"
    ("uplevel" body line 2)
    invoked from within
"uplevel 1 $body"
Error: Follow https://guide.macports.org/#project.tickets to report a bug.

Verification of rrdtool installation and location

$ which rrdtool
/opt/local/bin/rrdtool

I even tried this

port -v -d upgrade ntop --with-rrd-home=/opt/local/bin/rrdtool, but I got the same error message above.

main.log file attached

[TheLastLovemark]

ntop main.log

[mf2k (Frank Schima)]

Duplicate of #55550.