What could DUP mean when using ping?
What could DUP mean when using ping?
ping
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
add a comment |
What could DUP mean when using ping?
ping
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
add a comment |
What could DUP mean when using ping?
ping
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
What could DUP mean when using ping?
ping
ping
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
edited May 16 '11 at 12:23
Tshepang
26.3k72186264
26.3k72186264
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
asked May 16 '11 at 11:09
LanceBaynesLanceBaynes
10.7k76199325
10.7k76199325
add a comment |
add a comment |
3 Answers
3
active
oldest
votes
DUP means duplicate packet.
From man ping:
Duplicate and Damaged Packets
ping will report duplicate and damaged
packets. Duplicate packets should
never occur, and seem to be caused by
inappropriate link-level
retransmissions. Duplicates may occur
in many situations and are rarely (if
ever) a good sign, although the
presence of low levels of duplicates
may not always be cause for alarm.
Damaged packets are obviously serious
cause for alarm and often indicate
broken hardware somewhere in the ping
packet's path (in the network or in
the hosts).
There are different reasons for this, did you capture your network traffic with an interface in promiscous mode? Sometimes this is the reason for dupplicated packets.
answered May 16 '11 at 11:16
echoxechox
13k43953
I have an interface in promiscous mode. I receievDUPpackets inping. So what's happening in this case?. I have a raw socket program that sends the received packets to thetun/tapinterface. Ping is done throughtapinterface which will be sent viaraw socketthrough the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.
– Ramana Reddy
Jun 20 '17 at 12:44
add a comment |
It means the reply packet is a duplicate. ICMP responses contain a sequence number. Sometimes you'll actually get more than one reply with the same sequence number. This is usually caused by faulty networks. Wireless networks often rely on re-sending packets if they don't get proper verification, and if the first one actually worked, the re-send will be a duplicate. In normal usage duplicates are discarded. In ping replies they are noted because they tell you something about how the network is functioning. For example, if you are getting 100% duplicates some fault detection mechanism is likely broken.
edited 3 hours ago
crizCraig
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
add a comment |
Check out if couple machines aren't using same IP. It was my case for that message.
I run into this when I cloned a vm machine and run both at the same time. Network configuration was in a bridge mode and IP linked to mac. So when second machine start using network I experienced problems with ssh:
write: Connection reset by peer
ssh: connect to host 172.16.13.105 port 22: Connection refused
ssh_exchange_identification: read: Connection reset by peer
And the ping error when ping. Hope it will help someone.
edited Nov 27 '18 at 13:40
tymik
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
DUP means duplicate packet.
From man ping:
Duplicate and Damaged Packets
ping will report duplicate and damaged
packets. Duplicate packets should
never occur, and seem to be caused by
inappropriate link-level
retransmissions. Duplicates may occur
in many situations and are rarely (if
ever) a good sign, although the
presence of low levels of duplicates
may not always be cause for alarm.
Damaged packets are obviously serious
cause for alarm and often indicate
broken hardware somewhere in the ping
packet's path (in the network or in
the hosts).
There are different reasons for this, did you capture your network traffic with an interface in promiscous mode? Sometimes this is the reason for dupplicated packets.
answered May 16 '11 at 11:16
echoxechox
13k43953
I have an interface in promiscous mode. I receievDUPpackets inping. So what's happening in this case?. I have a raw socket program that sends the received packets to thetun/tapinterface. Ping is done throughtapinterface which will be sent viaraw socketthrough the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.
– Ramana Reddy
Jun 20 '17 at 12:44
add a comment |
DUP means duplicate packet.
From man ping:
Duplicate and Damaged Packets
ping will report duplicate and damaged
packets. Duplicate packets should
never occur, and seem to be caused by
inappropriate link-level
retransmissions. Duplicates may occur
in many situations and are rarely (if
ever) a good sign, although the
presence of low levels of duplicates
may not always be cause for alarm.
Damaged packets are obviously serious
cause for alarm and often indicate
broken hardware somewhere in the ping
packet's path (in the network or in
the hosts).
There are different reasons for this, did you capture your network traffic with an interface in promiscous mode? Sometimes this is the reason for dupplicated packets.
answered May 16 '11 at 11:16
echoxechox
13k43953
I have an interface in promiscous mode. I receievDUPpackets inping. So what's happening in this case?. I have a raw socket program that sends the received packets to thetun/tapinterface. Ping is done throughtapinterface which will be sent viaraw socketthrough the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.
– Ramana Reddy
Jun 20 '17 at 12:44
add a comment |
DUP means duplicate packet.
From man ping:
Duplicate and Damaged Packets
ping will report duplicate and damaged
packets. Duplicate packets should
never occur, and seem to be caused by
inappropriate link-level
retransmissions. Duplicates may occur
in many situations and are rarely (if
ever) a good sign, although the
presence of low levels of duplicates
may not always be cause for alarm.
Damaged packets are obviously serious
cause for alarm and often indicate
broken hardware somewhere in the ping
packet's path (in the network or in
the hosts).
There are different reasons for this, did you capture your network traffic with an interface in promiscous mode? Sometimes this is the reason for dupplicated packets.
answered May 16 '11 at 11:16
echoxechox
13k43953
DUP means duplicate packet.
From man ping:
Duplicate and Damaged Packets
ping will report duplicate and damaged
packets. Duplicate packets should
never occur, and seem to be caused by
inappropriate link-level
retransmissions. Duplicates may occur
in many situations and are rarely (if
ever) a good sign, although the
presence of low levels of duplicates
may not always be cause for alarm.
Damaged packets are obviously serious
cause for alarm and often indicate
broken hardware somewhere in the ping
packet's path (in the network or in
the hosts).
There are different reasons for this, did you capture your network traffic with an interface in promiscous mode? Sometimes this is the reason for dupplicated packets.
answered May 16 '11 at 11:16
echoxechox
13k43953
answered May 16 '11 at 11:16
echoxechox
13k43953
answered May 16 '11 at 11:16
echoxechox
13k43953
answered May 16 '11 at 11:16
echoxechox
13k43953
13k43953
I have an interface in promiscous mode. I receievDUPpackets inping. So what's happening in this case?. I have a raw socket program that sends the received packets to thetun/tapinterface. Ping is done throughtapinterface which will be sent viaraw socketthrough the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.
– Ramana Reddy
Jun 20 '17 at 12:44
add a comment |
I have an interface in promiscous mode. I receievDUPpackets inping. So what's happening in this case?. I have a raw socket program that sends the received packets to thetun/tapinterface. Ping is done throughtapinterface which will be sent viaraw socketthrough the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.
– Ramana Reddy
Jun 20 '17 at 12:44
I have an interface in promiscous mode. I receiev
DUP packets in ping. So what's happening in this case?. I have a raw socket program that sends the received packets to the tun/tap interface. Ping is done through tap interface which will be sent via raw socket through the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.– Ramana Reddy
Jun 20 '17 at 12:44
I have an interface in promiscous mode. I receiev
DUP packets in ping. So what's happening in this case?. I have a raw socket program that sends the received packets to the tun/tap interface. Ping is done through tap interface which will be sent via raw socket through the interface that is in promiscous mode. If that interface is not in promiscous mode I am unable to receive ping reply.– Ramana Reddy
Jun 20 '17 at 12:44
add a comment |
It means the reply packet is a duplicate. ICMP responses contain a sequence number. Sometimes you'll actually get more than one reply with the same sequence number. This is usually caused by faulty networks. Wireless networks often rely on re-sending packets if they don't get proper verification, and if the first one actually worked, the re-send will be a duplicate. In normal usage duplicates are discarded. In ping replies they are noted because they tell you something about how the network is functioning. For example, if you are getting 100% duplicates some fault detection mechanism is likely broken.
edited 3 hours ago
crizCraig
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
add a comment |
It means the reply packet is a duplicate. ICMP responses contain a sequence number. Sometimes you'll actually get more than one reply with the same sequence number. This is usually caused by faulty networks. Wireless networks often rely on re-sending packets if they don't get proper verification, and if the first one actually worked, the re-send will be a duplicate. In normal usage duplicates are discarded. In ping replies they are noted because they tell you something about how the network is functioning. For example, if you are getting 100% duplicates some fault detection mechanism is likely broken.
edited 3 hours ago
crizCraig
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
add a comment |
It means the reply packet is a duplicate. ICMP responses contain a sequence number. Sometimes you'll actually get more than one reply with the same sequence number. This is usually caused by faulty networks. Wireless networks often rely on re-sending packets if they don't get proper verification, and if the first one actually worked, the re-send will be a duplicate. In normal usage duplicates are discarded. In ping replies they are noted because they tell you something about how the network is functioning. For example, if you are getting 100% duplicates some fault detection mechanism is likely broken.
edited 3 hours ago
crizCraig
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
It means the reply packet is a duplicate. ICMP responses contain a sequence number. Sometimes you'll actually get more than one reply with the same sequence number. This is usually caused by faulty networks. Wireless networks often rely on re-sending packets if they don't get proper verification, and if the first one actually worked, the re-send will be a duplicate. In normal usage duplicates are discarded. In ping replies they are noted because they tell you something about how the network is functioning. For example, if you are getting 100% duplicates some fault detection mechanism is likely broken.
edited 3 hours ago
crizCraig
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
edited 3 hours ago
crizCraig
1033
edited 3 hours ago
crizCraig
1033
edited 3 hours ago
crizCraig
1033
1033
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
answered May 16 '11 at 11:18
CalebCaleb
51.5k9149194
51.5k9149194
add a comment |
add a comment |
Check out if couple machines aren't using same IP. It was my case for that message.
I run into this when I cloned a vm machine and run both at the same time. Network configuration was in a bridge mode and IP linked to mac. So when second machine start using network I experienced problems with ssh:
write: Connection reset by peer
ssh: connect to host 172.16.13.105 port 22: Connection refused
ssh_exchange_identification: read: Connection reset by peer
And the ping error when ping. Hope it will help someone.
edited Nov 27 '18 at 13:40
tymik
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
add a comment |
Check out if couple machines aren't using same IP. It was my case for that message.
I run into this when I cloned a vm machine and run both at the same time. Network configuration was in a bridge mode and IP linked to mac. So when second machine start using network I experienced problems with ssh:
write: Connection reset by peer
ssh: connect to host 172.16.13.105 port 22: Connection refused
ssh_exchange_identification: read: Connection reset by peer
And the ping error when ping. Hope it will help someone.
edited Nov 27 '18 at 13:40
tymik
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
add a comment |
Check out if couple machines aren't using same IP. It was my case for that message.
I run into this when I cloned a vm machine and run both at the same time. Network configuration was in a bridge mode and IP linked to mac. So when second machine start using network I experienced problems with ssh:
write: Connection reset by peer
ssh: connect to host 172.16.13.105 port 22: Connection refused
ssh_exchange_identification: read: Connection reset by peer
And the ping error when ping. Hope it will help someone.
edited Nov 27 '18 at 13:40
tymik
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
Check out if couple machines aren't using same IP. It was my case for that message.
I run into this when I cloned a vm machine and run both at the same time. Network configuration was in a bridge mode and IP linked to mac. So when second machine start using network I experienced problems with ssh:
write: Connection reset by peer
ssh: connect to host 172.16.13.105 port 22: Connection refused
ssh_exchange_identification: read: Connection reset by peer
And the ping error when ping. Hope it will help someone.
edited Nov 27 '18 at 13:40
tymik
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
edited Nov 27 '18 at 13:40
tymik
14018
edited Nov 27 '18 at 13:40
tymik
14018
edited Nov 27 '18 at 13:40
tymik
14018
14018
answered Jan 30 '15 at 10:43
bambychabambycha
391
answered Jan 30 '15 at 10:43
bambychabambycha
391
answered Jan 30 '15 at 10:43
bambychabambycha
391
391
add a comment |
add a comment |
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