RTシリーズのNATとIPマスカレードに関するFAQ
pass-logフィルタを用いてpingを観測しよう!
作成日 | 1999/Jul/29 |
最終変更日 | 2022/Dec/28 |
文書サイズ | 23KB |
pingのパケットを観測する方法を教えてください。
[ 目次 ]
[ pingのしくみ ]
pingは、通信が可能かどうか(到達可能性)を調べる機能で、 「Echo Request」のICMPパケットを相手に送信し、 「Echo Reply」のICMPパケットが戻ってきたら、 通信可能と判断します。 この時の「Echo Request」のICMPパケットを送信してから 「Echo Reply」のICMPパケットを受信するまでの 時間を測定して、応答時間(遅延時間)とします。
ICMPメッセージのタイプ番号が8であるICMPパケット。
正確には「ICMP Echo Request Message」と表記される
ICMPメッセージのタイプ番号が0であるICMPパケット。
正確には「ICMP Echo Reply Message」と表記される
[ IP機器(A):ping要求側 ] ┃ ┃ [ IP機器(B):ping応答側 ] ┃ ┃ ・ICMP Echo Requestを発信し┃ ┃ 時間測定を開始する ┃ ┃ ↓ ┃ ICMP Echo Request ┃ ↓ ┃ →→→→→→→→ ┃ ↓ ┃ ┃・ICMP Echo Requestを受信 ↓<応答時間の測定中> ┃ ┃ 応答パケットである ↓ ┃ ┃ ICMP Echo Replyを送信 ↓ ┃ ICMP Echo Reply ┃ ↓ ┃ ←←←←←←←← ┃ ・ICMP Echo Replyを受信する┃ ┃ ┃ ┃ ・測定した時間を応答時間と ┃ ┃ する ┃ ┃ ┃ ┃
[ IP機器(A):ping要求側 ] ┃ ┃ [ IP機器(B):DNSサーバ ] ┃ ┃ ・ping相手のIPアドレスをDNS┃ ┃ 名から調べる為DNSサーバに┃ ┃ 問い合わせる ┃ ┃ ┃ DNS Query ┃ ┃ →→→→→→→→ ┃ ┃ ┃・DNSの問い合せに対して ┃ ┃ 応答する ┃ DNS Response ┃ ┃ ←←←←←←←← ┃ ・ping相手のIPアドレスが判 ┃ ┃ 明した。 ┃ ┃ ┃ ┃ ┃ ┃ [ IP機器(C):ping応答側 ] ・ICMP Echo Requestを発信し┃ ┃ 時間測定を開始する ┃ ┃ ↓ ┃ ICMP Echo Request ┃ ↓ ┃ →→→→→→→→ ┃ ↓ ┃ ┃・ICMP Echo Requestを受信 ↓<応答時間の測定中> ┃ ┃ 応答パケットである ↓ ┃ ┃ ICMP Echo Replyを送信 ↓ ┃ ICMP Echo Reply ┃ ↓ ┃ ←←←←←←←← ┃ ・ICMP Echo Replyを受信する┃ ┃ ┃ ┃ ・測定した時間を応答時間と ┃ ┃ する ┃ ┃ ┃ ┃
[ テスト環境 ]
+-------------+ | IPホスト#A | (www.rtpro.yamaha.co.jp) +------+------+ | 133.176.200.51 133.176.200.0/24 -------+----------------------------------- | 133.176.200.67 +------+------+ | RT(A) | (ダイヤルアップ・サーバ) +-------------+ : 10/Celery : ISDN擬似交換機またはISDN回線 〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜 : : 20/Tomato +-------------+ (133.176.200.68) | RT(B) | (端末型ダイヤルアップ) ↑ IPマスカレード +------+------+ 192.168.0.1-192.168.0.254 | 192.168.0.1 192.168.0.0/24 -------+----------------------------------- | 192.168.0.2 +------+------+ | IPホスト#B | (Windows98) +-------------+
isdn local address 10/Celery ip lan address 133.176.200.67/24 ip lan proxyarp on pp select anonymous ip pp remote address pool 133.176.200.68 133.176.200.69 pp auth request chap-pap pp auth username test-user test-password ppp ipcp msext on pp enable anonymous dns server 133.176.200.51 dns domain rtpro.yamaha.co.jp
isdn local address 20/Tomato ip lan address 192.168.0.1/24 pp select 1 isdn remote address call 10/Celery ip pp route add net default 1 pp auth accept chap pap pp auth myname test-user test-password nat use on nat masquerade on ppp ipcp ipaddress on ppp ipcp msext on pp enable 1 dhcp service server dhcp scope 1 192.168.0.2-192.168.0.254/24 dns server 133.176.200.51 dns domain rtpro.yamaha.co.jp dns private address spoof on
isdn local address 10/Celery ip lan address 133.176.200.67/24 ip lan proxyarp on pp select anonymous ip pp remote address pool 133.176.200.68 133.176.200.69 pp auth request chap-pap pp auth username test-user test-password ppp ipcp msext on pp enable anonymous dns server 133.176.200.51 dns domain rtpro.yamaha.co.jp
isdn local address 20/Tomato ip lan address 192.168.0.1/24 nat descriptor type 1 masquerade pp select 1 isdn remote address call 10/Celery ip pp route add net default 1 pp auth accept chap pap pp auth myname test-user test-password ip pp nat descriptor 1 ppp ipcp ipaddress on ppp ipcp msext on pp enable 1 dhcp service server dhcp scope 1 192.168.0.2-192.168.0.254/24 dns server 133.176.200.51 dns domain rtpro.yamaha.co.jp dns private address spoof on
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃C:\WINDOWS> ping 192.168.0.1 ┃ ┃Pinging 192.168.0.1 with 32 bytes of data: ┃ ┃Reply from 192.168.0.1: bytes=32 time=1ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=2ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=1ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=1ms TTL=64 ┃ ┃Ping statistics for 192.168.0.1: ┃ Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), ┃Approximate round trip times in milli-seconds: ┃ Minimum = 1ms, Maximum = 2ms, Average = 1ms ┃ ┃C:\WINDOWS> ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃C:\WINDOWS> ping 133.176.200.51 ┃ ┃Pinging 133.176.200.51 with 32 bytes of data: ┃ ┃Reply from 133.176.200.51: bytes=32 time=146ms TTL=253 ┃Reply from 133.176.200.51: bytes=32 time=13ms TTL=253 ┃Reply from 133.176.200.51: bytes=32 time=14ms TTL=253 ┃Reply from 133.176.200.51: bytes=32 time=13ms TTL=253 ┃ ┃Ping statistics for 133.176.200.51: ┃ Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), ┃Approximate round trip times in milli-seconds: ┃ Minimum = 13ms, Maximum = 146ms, Average = 46ms ┃ ┃C:\WINDOWS> ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
1999/06/23 09:28:51: PP[01] IP Commencing: ICMP 192.168.0.2 > 133.176.200.51 : echo request 1999/06/23 09:28:51: PP[01] Calling 10 with 1B mode 1999/06/23 09:28:51: PP[01] PPP/IPCP up ... 1999/06/23 09:29:54: PP[01] Disconnect complete 1999/06/23 09:29:54: PP[01] Disconnected cause [No error.] 1999/06/23 09:29:54: PP[01] Disconnected by [User] 1999/06/23 09:29:54: PP[01] Charge is 10 yen ...
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃# ip filter 1 pass-log * * * * * ┃# ip lan secure filter in 1 ┃# ip lan secure filter out 1 ┃# syslog notice on ┃# clear log ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
ip filter 1 pass-log * * icmp * *
ip filter 1 pass-log * * icmp-info * *
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃C:\WINDOWS> ping 192.168.0.1 ┃ ┃Pinging 192.168.0.1 with 32 bytes of data: ┃ ┃Reply from 192.168.0.1: bytes=32 time=3ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=4ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=3ms TTL=64 ┃Reply from 192.168.0.1: bytes=32 time=3ms TTL=64 ┃ ┃Ping statistics for 192.168.0.1: ┃ Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), ┃Approximate round trip times in milli-seconds: ┃ Minimum = 3ms, Maximum = 4ms, Average = 3ms ┃ ┃C:\WINDOWS> ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
# show log 1999/06/23 13:22:19: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 192.168.0.1 : echo request 1999/06/23 13:22:19: LAN1 Passed at OUT(1) filter: ICMP 192.168.0.1 > 192.168.0.2 : echo reply 1999/06/23 13:22:20: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 192.168.0.1 : echo request 1999/06/23 13:22:20: LAN1 Passed at OUT(1) filter: ICMP 192.168.0.1 > 192.168.0.2 : echo reply 1999/06/23 13:22:21: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 192.168.0.1 : echo request 1999/06/23 13:22:21: LAN1 Passed at OUT(1) filter: ICMP 192.168.0.1 > 192.168.0.2 : echo reply 1999/06/23 13:22:22: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 192.168.0.1 : echo request 1999/06/23 13:22:22: LAN1 Passed at OUT(1) filter: ICMP 192.168.0.1 > 192.168.0.2 : echo reply ...
[ DNS名を指定してpingする ]
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃# ip filter 1 pass-log * * * * * ┃# ip lan secure filter in 1 ┃# ip lan secure filter out 1 ┃# syslog notice on ┃# clear log ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ┃ ┃C:\WINDOWS> ping www.rtpro.yamaha.co.jp ┃ ┃Pinging www.rtpro.yamaha.co.jp [133.176.200.51] with 32 bytes of data: ┃ ┃Reply from 133.176.200.51: bytes=32 time=26ms TTL=252 ┃Reply from 133.176.200.51: bytes=32 time=16ms TTL=252 ┃Reply from 133.176.200.51: bytes=32 time=16ms TTL=252 ┃Reply from 133.176.200.51: bytes=32 time=17ms TTL=252 ┃ ┃Ping statistics for 133.176.200.51: ┃ Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), ┃Approximate round trip times in milli-seconds: ┃ Minimum = 16ms, Maximum = 26ms, Average = 18ms ┃ ┃C:\WINDOWS> ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
# show log 1999/06/23 15:20:07: LAN1 Passed at IN(1) filter: UDP 192.168.0.2:1039 > 192.168.0.1:53 (DNS Query [www.rtpro.yamaha.co.jp]) 1999/06/23 15:20:07: PP[01] IP Commencing: UDP 192.168.0.1:53 > 133.176.200.51:53 (DNS Query [www.rtpro.yamaha.co.jp] from 192.168.0.2) 1999/06/23 15:20:07: PP[01] Calling 10 with 1B mode 1999/06/23 15:20:07: PP[01] PPP/IPCP up 1999/06/23 15:20:11: LAN1 Passed at OUT(1) filter: UDP 192.168.0.1:53 > 192.168.0.2:1039 (DNS response) 1999/06/23 15:20:11: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 133.176.200.51 : echo request 1999/06/23 15:20:11: LAN1 Passed at OUT(1) filter: ICMP 133.176.200.51 > 192.168.0.2 : echo reply 1999/06/23 15:20:12: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 133.176.200.51 : echo request 1999/06/23 15:20:12: LAN1 Passed at OUT(1) filter: ICMP 133.176.200.51 > 192.168.0.2 : echo reply 1999/06/23 15:20:13: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 133.176.200.51 : echo request 1999/06/23 15:20:13: LAN1 Passed at OUT(1) filter: ICMP 133.176.200.51 > 192.168.0.2 : echo reply 1999/06/23 15:20:14: LAN1 Passed at IN(1) filter: ICMP 192.168.0.2 > 133.176.200.51 : echo request 1999/06/23 15:20:14: LAN1 Passed at OUT(1) filter: ICMP 133.176.200.51 > 192.168.0.2 : echo reply ...
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