[mrtg] mrtg 2.17.7 IPv6 Centos

[tslbai]

Hi,

i'm running a server on CentOS 7.6(1810) and installed mrtg 2.17.7
sucessfully.

I have a simple IPv4-and IPv6-Konfig.
IPv4 works; IPv6 fails.

### IPv4-Konfig - works with some error-messages
####################################
EnableIPv6: yes
WorkDir: /www/vhosts/www.xyz.de/htdocs/mrtg
ImageDir: /www/vhosts/www.xyz.de/htdocs/mrtg/images
LogDir: /var/lib/mrtg
ThreshDir: /var/lib/mrtg
MaxBytes[_]: 1250000
Options[_]: growright, bits
Target[test-gw1-vlan1]: ifInOctets.7&ifOutOctets.7:xyz123 at 192.168.25.25
Title[test-gw1-vlan1]: bai-gw1 vlan1
PageTop[test-gw1-vlan1]: <H1>bai-gw1 vlan1</H1>

# env LANG=C /usr/local/mrtg2177/bin/mrtg /usr/local/mrtg2177/etc/mrtg.cfg
Subroutine IO::Socket::INET6::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine IO::Socket::INET6::unpack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine IO::Socket::INET6::sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine SNMP_Session::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/../lib/mrtg2/SNMP_Session.pm line 149.
Subroutine SNMPv1_Session::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/../lib/mrtg2/SNMP_Session.pm line 604.
Subroutine main::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
Subroutine main::unpack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
Subroutine main::sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
#####################################################################





### IPv6-Konfig - doesnt work
EnableIPv6: yes
WorkDir: /www/vhosts/www.xyz.de/htdocs/mrtg
ImageDir: /www/vhosts/www.xyz.de/htdocs/mrtg/images
LogDir: /var/lib/mrtg
ThreshDir: /var/lib/mrtg
MaxBytes[_]: 1250000
Options[_]: growright, bits
Target[test6-gw1-vlan1]:
ifInOctets.7&ifOutOctets.7:xyz123@[2001:db8:900f::f001]
Title[test6-gw1-vlan1]: bai6-gw1 vlan1
PageTop[test6-gw1-vlan1]: <H1>bai6-gw1 vlan1</H1>

# env LANG=C /usr/local/mrtg2177/bin/mrtg /usr/local/mrtg2177/etc/mrtg.cfg
Subroutine IO::Socket::INET6::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine IO::Socket::INET6::unpack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine IO::Socket::INET6::sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/share/perl5/IO/Socket/INET6.pm line 16.
Subroutine SNMP_Session::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/../lib/mrtg2/SNMP_Session.pm line 149.
Subroutine SNMPv1_Session::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/../lib/mrtg2/SNMP_Session.pm line 604.
Subroutine main::pack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
Subroutine main::unpack_sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
Subroutine main::sockaddr_in6 redefined at
/usr/share/perl5/vendor_perl/Exporter.pm line 66.
 at /usr/local/mrtg2177/bin/mrtg line 305.
Undefined subroutine &SNMP_Session::inet_ntop called at
/usr/local/mrtg2177/bin/../lib/mrtg2/SNMP_Session.pm line 549.

No files are written to workdir.
In tcpdump i can see that via IPv6 no packets are sent to the target.
With ping6, snmpwalk etc. is the target reacheble.


Could you please give me a hint for debugging?

Thanks & Bye,
Florian