Cisco Cisco ASA for Nexus 1000V Series Switch Troubleshooting Guide

(frag 48872:1480@1480+) (ttl 255)

4: 11:30:30.309935 5475.d029.8916 0017.0f17.af80 0x0800 1054: 10.23.124.1 > 10.99.103.6:

(frag 48872:1020@2960) (ttl 255)

...

ASA# show cap out detail

30 packets captured

1: 11:30:30.309035 5475.d029.8917 001a.a185.847f 0x0800 1514: 10.23.124.142 > 10.23.124.1:

icmp: echo request (wrong icmp csum) (frag 48872:1480@0+) (ttl 255)

2: 11:30:30.309035 5475.d029.8917 001a.a185.847f 0x0800 1514: 10.23.124.142 > 10.23.124.1:

(frag 48872:1480@1480+) (ttl 255)

3: 11:30:30.309050 5475.d029.8917 001a.a185.847f 0x0800 1054: 10.23.124.142 > 10.23.124.1:

(frag 48872:1020@2960) (ttl 255)

4: 11:30:30.309859 001a.a185.847f 5475.d029.8917 0x0800 1514: 10.23.124.1 > 10.23.124.142:

icmp: echo reply (wrong icmp csum) (frag 48872:1480@0+) (ttl 255)

5: 11:30:30.309859 001a.a185.847f 5475.d029.8917 0x0800 1514: 10.23.124.1 > 10.23.124.142:

(frag 48872:1480@1480+) (ttl 255)

6: 11:30:30.309859 001a.a185.847f 5475.d029.8917 0x0800 1054: 10.23.124.1 > 10.23.124.142:

(frag 48872:1020@2960) (ttl 255)

This is an example showing an ASA receiving a jumbo frame on the inside interface too large to transmit out
the egress interface, and the packet has the DF bit set. The packet is dropped and the ICMP type 3 code 4
error message is transmitted towards the inside host:

ASA# show cap in detail

6 packets captured

1: 11:42:10.147422 0017.0f17.af80 5475.d029.8916 0x0800 4014: 10.99.103.6 > 10.23.124.1:

icmp: echo request (DF) (ttl 255, id 48887)

2: 11:42:10.147605 5475.d029.8916 0017.0f17.af80 0x0800 70: 10.99.29.1 > 10.99.103.6:

icmp: 10.23.124.1 unreachable − need to frag (mtu 1500) (ttl 72, id 56194)

3: 11:42:10.150199 0017.0f17.af80 5475.d029.8916 0x0800 4014: 10.99.103.6 > 10.23.124.1:

icmp: echo request (DF) (ttl 255, id 48888)

4: 11:42:12.146476 0017.0f17.af80 5475.d029.8916 0x0800 4014: 10.99.103.6 > 10.23.124.1:

icmp: echo request (DF) (ttl 255, id 48889)

5: 11:42:12.146553 5475.d029.8916 0017.0f17.af80 0x0800 70: 10.99.29.1 > 10.99.103.6:

icmp: 10.23.124.1 unreachable − need to frag (mtu 1500) (ttl 72, id 45247)

6: 11:42:12.152427 0017.0f17.af80 5475.d029.8916 0x0800 4014: 10.99.103.6 > 10.23.124.1:

icmp: echo request (DF) (ttl 255, id 48890)

6 packets shown

ASA# show cap out detail

0 packet captured

0 packet shown

ASA#

Related Information

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