WLAN client -> WLAN client ping不会产生“回应应答”

Question

我的无线局域网客户端连接到AT&T U-Verse Arris NVG589。当我尝试在家里的WLAN上ping我的Mac时，没有得到响应。

tcpdump 'icmp[icmptype] = icmp-echo or icmp[icmptype] = icmp-echoreply'
tcpdump: data link type PKTAP
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on pktap, link-type PKTAP (Packet Tap), capture size 262144 bytes

从这台Mac到www.google.com的ping命令有效：

21:46:20.817743 IP work-mbp.attlocal.net > yv-in-f103.1e100.net: ICMP echo request, id 55595, seq 0, length 64
21:46:20.842309 IP yv-in-f103.1e100.net > work-mbp.attlocal.net: ICMP echo reply, id 55595, seq 0, length 64
21:46:21.820431 IP work-mbp.attlocal.net > yv-in-f103.1e100.net: ICMP echo request, id 55595, seq 1, length 64
21:46:21.844247 IP yv-in-f103.1e100.net > work-mbp.attlocal.net: ICMP echo reply, id 55595, seq 1, length 64

在WLAN上从一台Mac到另一台Mac的ping没有显示“回应应答”：

21:34:34.994444 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 0, length 16
21:34:35.989923 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 1, length 16
21:34:37.978274 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 2, length 16
21:34:40.213181 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 3, length 16
21:34:41.978188 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 4, length 16
21:34:43.978284 IP homempb.attlocal.net > work-mbp.attlocal.net: ICMP echo request, id 12, seq 5, length 16

El Capitan防火墙已禁用。

Answer 1

原来数据包筛选器已启用，并且仅允许internet绑定ping：

pfctl -a '*' -s rules

显示了此规则：

pass out inet proto icmp all keep state

我使用以下命令临时禁用了数据包筛选器：

pfctl -d 

ping“回音应答”开始出现。