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Old 09-22-2017, 10:52 PM   #1
gbcbooks
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icmp requset packet send from eth0 and icmp reply packet receive from eth1,why linux ingore it


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as the topology ,

i use "ping -I eth1 9.9.9.9 " on JP , and watch tcpdump -i eth0 "icmp && host 9.9.9.9",

tcpdump was able to capture icmp reply packet , but ping was ingoring it .

i have enable net.conf.ipv4.ip_forward=1 and net.conf.ipv4.all.rp_filter=0

any one can tell me what is going on ?

Last edited by gbcbooks; 09-22-2017 at 11:02 PM.
 
Old 09-23-2017, 07:32 AM   #2
lazydog
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Firewall running?
 
Old 09-25-2017, 11:57 AM   #3
gbcbooks
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firewall was running , but firewall rule did not drop the packet . and i did not find any log about the icmp in the /var/log/kern.log file.
 
Old 09-25-2017, 12:38 PM   #4
lazydog
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Look at your routing table you might find that packets are not traversing the way you think they should.
 
Old 09-25-2017, 03:38 PM   #5
camp0
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Put your firewall rules and your routing table helps
 
Old 09-26-2017, 07:16 AM   #6
voleg
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Using IP addresses from same subnet usually cause that.
If you need more IP from same subnet, use IP alias.
If you need redundancy or throughput by using two cards, use bond.
 
  


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