linux - How can I filter the output from a multicast ping6 to all nodes to get all reachable IPv6 Devices in one moment in time?

How can I filter the Output from a multicast ping to all nodes so that in the output file every IP appears only once?

1. If a new device joins the network its written to a file with a joining Timestamp.


2. If a device leaves the Network its gets removed from that file.


3. At the end the Output file show me the current reachable Devices in the Network with the joining Timestamp

     ping6 -I eth1 ip6-allnodes
        PING ip6-allnodes(ip6-allnodes) from fe80::aaaa:aaaa:aaaa:aaaa eth1: 56 data bytes
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=1 ttl=64 time=0.018 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=1 ttl=64 time=0.490 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=1 ttl=64 time=0.739 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=2 ttl=64 time=0.037 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=2 ttl=64 time=0.513 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=2 ttl=64 time=0.674 ms (DUP!)
        64 bytes from fe80::dddd:dddd:dddd:dddd: icmp_seq=2 ttl=64 time=228 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=3 ttl=64 time=0.033 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=3 ttl=64 time=0.460 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=3 ttl=64 time=0.611 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=4 ttl=64 time=0.045 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=4 ttl=64 time=0.485 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=4 ttl=64 time=0.609 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=5 ttl=64 time=0.035 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=5 ttl=64 time=0.518 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=5 ttl=64 time=0.580 ms (DUP!)
        64 bytes from fe80::eeee:eeee:eeee:eeee: icmp_seq=5 ttl=255 time=201 ms (DUP!)
        64 bytes from fe80::dddd:dddd:dddd:dddd: icmp_seq=5 ttl=64 time=237 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=6 ttl=64 time=0.032 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=6 ttl=64 time=0.508 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=6 ttl=64 time=0.540 ms (DUP!)
        64 bytes from fe80::aaaa:aaaa:aaaa:aaaa: icmp_seq=7 ttl=64 time=0.038 ms
        64 bytes from fe80::bbbb:bbbb:bbbb:bbbb: icmp_seq=7 ttl=64 time=0.550 ms (DUP!)
        64 bytes from fe80::cccc:cccc:cccc:cccc: icmp_seq=7 ttl=64 time=0.640 ms (DUP!)
        64 bytes from fe80::dddd:dddd:dddd:dddd: icmp_seq=7 ttl=64 time=76.6 ms (DUP!)
        ip6-allnodes ping statistics ---
        7 packets transmitted, 7 received, +18 duplicates, 0% packet loss, time 6020ms
        rtt min/avg/max/mdev = 0.018/30.086/237.386/72.776 ms