__特___集__
この記事は、改訂＆リニューアルして『P はプロトコルのP - UDLD を究める』へ移転しました。
UDLD を究める(16)UDLD のデバッグ(2)Unidirectional を検知する
debug コマンドを使って、Unidirectional を検知してから、ErrDisable されるまでの流れを見ていきます。
※ 本ページでは、Debug コマンドを使用します。
本ページの内容を実際に試される場合は、事前に「Debug コマンドについて」をお読みください。
Catalyst#debug udld events
UDLD events debugging is on
Catalyst#debug udld packets
UDLD packets debugging is on
Catalyst#
ログ中の色づけされた16進数は、以下のとおりです。
- Device ID
Port ID
Echo
Message Interval
Flags
Catalyst-A
Bidirectional になっています。
*Mar 17 03:56:00: allNeighborsAgedOutEvent during link up. (Gi0/11) ①
*Mar 17 03:56:00: Phase set from ADV to LUP because all neighbors aged out (Gi0/11) ②
*Mar 17 03:56:00: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11) ③
*Mar 17 03:56:00: Pr (Gi0/11)
*Mar 17 03:56:00: prev = 0 entry = 1141168 next = 0 exp_time = 0 (Gi0/11)
*Mar 17 03:56:00: udsb->cache = 0xDCA128 (Gi0/11)
*Mar 17 03:56:00: timeout timer = 7 (Gi0/11)
*Mar 17 03:56:00: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 17 03:56:00: Pr (Gi0/11)
*Mar 17 03:56:01: timeout timer = 6 (Gi0/11)
*Mar 17 03:56:01: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 17 03:56:01: Pr (Gi0/11)
*Mar 17 03:56:02: timeout timer = 5 (Gi0/11)
*Mar 17 03:56:02: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 17 03:56:02: Pr (Gi0/11)
① 対向機器からUDLD PDU を受信しなくなり、エントリーをテーブルから消去しました。
② Link Up フェイズへ移行しました。
③ 空のEcho TLV を持ったProbe を送信し始めます。 Recommended Timeout フラグとReSynch フラグが立っています。
Catalyst-B
*Mar 17 03:56:00: udld process packet received, length 99 (Gi0/12) ①
*Mar 17 03:56:00: 21 03 6E 0A 00 01 00 0F 46 41 41 30 35 34 39 53 30 41 54 00
*Mar 17 03:56:00: 02 00 0A 47 69 30 2F 31 31 00 03 00 08 00 00 00 00 00 04 00
*Mar 17 03:56:00: 05 07 00 05 00 05 05 00 06 00 16 43 61 74 61 6C 79 73 74 33
*Mar 17 03:56:00: 35 35 30 2D 31 32 54 3A 41 00 07 00 08 00 00 00 54
*Mar 17 03:56:00: TLV = 1 TLV length = 15 (Gi0/12)
*Mar 17 03:56:00: item_len[1] = 12 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 58 (Gi0/12)
*Mar 17 03:56:00: TLV = 2 TLV length = 10 (Gi0/12)
*Mar 17 03:56:00: item_len[2] = 7 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 48 (Gi0/12)
*Mar 17 03:56:00: TLV = 3 TLV length = 8 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 40 (Gi0/12)
*Mar 17 03:56:00: TLV = 4 TLV length = 5 (Gi0/12)
*Mar 17 03:56:00: item_len[4] = 1 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 35 (Gi0/12)
*Mar 17 03:56:00: TLV = 5 TLV length = 5 (Gi0/12)
*Mar 17 03:56:00: item_len[5] = 1 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 30 (Gi0/12)
*Mar 17 03:56:00: TLV = 6 TLV length = 22 (Gi0/12)
*Mar 17 03:56:00: item_len[6] = 19 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 8 (Gi0/12)
*Mar 17 03:56:00: TLV = 7 TLV length = 8 (Gi0/12)
*Mar 17 03:56:00: item_len[7] = 4 (Gi0/12)
*Mar 17 03:56:00: Bytes left = 0 (Gi0/12)
*Mar 17 03:56:00: Parse packet info and insert entry (0xDB6840) into cache. (Gi0/12)
*Mar 17 03:56:00: Cached TLV #1 = FAA0549S0AT, length = 11 (Gi0/12)
*Mar 17 03:56:00: Cached TLV #2 = Gi0/11, length = 6 (Gi0/12)
*Mar 17 03:56:00: udld_handle_bidirdetect_info (Gi0/12)
*Mar 17 03:56:00: udld_handle_bidirdetect_info pairs = 0 (Gi0/12)
*Mar 17 03:56:00: Cached TLV #4 = 7, length = 0 (Gi0/12)
*Mar 17 03:56:00: Cached TLV #5 = 5, length = 0 (Gi0/12)
*Mar 17 03:56:00: Cached TLV #6 = Catalyst3550-12T:A, length = 18 (Gi0/12)
*Mar 17 03:56:00: Cached TLV #7, val = 3 length = 84 (Gi0/12)
*Mar 17 03:56:00: New_entry = DB6840 (Gi0/12)
*Mar 17 03:56:00: Found an entry from same device (Gi0/12)
*Mar 17 03:56:00: Cached entries = 2 (Gi0/12)
*Mar 17 03:56:00: Entry (0xDA873C) deleted: 1 entries cached
*Mar 17 03:56:00: Cached entries = 1 (Gi0/12)
*Mar 17 03:56:00: Probe packet(resynch) (Gi0/12)
*Mar 17 03:56:00: Zero IDs in 2way conn list (Gi0/12)
*Mar 17 03:56:00: Doing neighbor scanning after bidir->non-bidir transition. (Gi0/12)
*Mar 17 03:56:00: Bidir->all unidir => DET. (Gi0/12)
*Mar 17 03:56:00: RSY neighbor (Gi0/12)
*Mar 17 03:56:00: Udld entering detection phase. (Gi0/12)
*Mar 17 03:56:00: UDLD send echo message, flags = 0 (Gi0/12)
*Mar 17 03:56:00: E (Gi0/12)
*Mar 17 03:56:00: Zero IDs in 2way conn list (Gi0/12)
*Mar 17 03:56:00: Zero IDs in 2way conn list (Gi0/12)
*Mar 17 03:56:00: UDLD FSM updated port, bi-flag udld_empty_echo, phase udld_detection (Gi0/12)③
*Mar 17 03:56:00: Udld receive packet *END*. (Gi0/12)②
（中略）
*Mar 17 03:56:05: confirmation recv'd in EXT (Gi0/12) ④
*Mar 17 03:56:05: UDLD disabled port, packet received in extended detection (Gi0/12)
*Mar 17 03:56:05: UDLD send flush message, flags = 0 (Gi0/12) ⑤
*Mar 17 03:56:05: F (Gi0/12)
*Mar 17 03:56:05: %UDLD-4-UDLD_PORT_DISABLED: UDLD disabled interface Gi0/12, unidirectional link detected ⑥
*Mar 17 03:56:05: %PM-4-ERR_DISABLE: udld error detected on Gi0/12, putting Gi0/12 in err-disable state
*Mar 17 03:56:05: Port UDLD set error disabled (Gi0/12)
*Mar 17 03:56:05: Entry (0xDB6840) deleted: 0 entries cached
*Mar 17 03:56:05: Hash entry deleted = DB6840 (Gi0/12)
*Mar 17 03:56:05: current phase = udld_disable_port (Gi0/12)
*Mar 17 03:56:05: Restart counter = 0 (Gi0/12)
*Mar 17 03:56:05: Neighbors counter = 0 (Gi0/12)
*Mar 17 03:56:05: Udld receive packet *END*. (Gi0/12)
*Mar 17 03:56:19: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/12, changed state to down
*Mar 17 03:56:19: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
*Mar 17 03:56:20: %LINK-3-UPDOWN: Interface GigabitEthernet0/12, changed state to down
① Catalyst-A から、Echo TLV が空のUDLD PDU を、GigabitEthernet0/12 で受信しました(Catalyst-A ログの③のフレームです)。
Recommended Timeout フラグとReSynch フラグが立っています。
② ここまでが一つのUDLD PDU です。
③ Detection フェイズへ移行しました。
④ 拡張ディテクションウィンドウが始まった直後に、空のEcho TLV を持ったProbe を受信しました。
⑤ Flush を送信しました。 F はFlush を意味します。
⑥ GigabitEthernet0/12 をErrDisable にしました。
アグレッシブモードの場合はどうでしょうか。
Catalyst-A
Bidirectional になっています。
*Mar 19 19:16:12: allNeighborsAgedOutEvent during link up. (Gi0/11) ①
*Mar 19 19:16:12: Phase set from ADV to LUP because all neighbors aged out (Gi0/11) ②
*Mar 19 19:16:12: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11) ③
*Mar 19 19:16:12: Pr (Gi0/11)
*Mar 19 19:16:12: prev = 0 entry = 11E588C next = 0 exp_time = 0 (Gi0/11)
*Mar 19 19:16:12: udsb->cache = 0xDCA128 (Gi0/11)
*Mar 19 19:16:12: timeout timer = 7 (Gi0/11)
*Mar 19 19:16:12: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:12: Pr (Gi0/11)
*Mar 19 19:16:13: timeout timer = 6 (Gi0/11)
*Mar 19 19:16:13: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:13: Pr (Gi0/11)
*Mar 19 19:16:14: timeout timer = 5 (Gi0/11)
*Mar 19 19:16:14: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:14: Pr (Gi0/11)
*Mar 19 19:16:15: timeout timer = 4 (Gi0/11)
*Mar 19 19:16:15: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:15: Pr (Gi0/11)
*Mar 19 19:16:16: timeout timer = 3 (Gi0/11)
*Mar 19 19:16:16: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:16: Pr (Gi0/11)
*Mar 19 19:16:17: timeout timer = 2 (Gi0/11)
*Mar 19 19:16:17: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:17: Pr (Gi0/11)
*Mar 19 19:16:18: timeout timer = 1 (Gi0/11)
*Mar 19 19:16:18: UDLD send probe message, flags = rec_timeout | resynch (Gi0/11)
*Mar 19 19:16:18: Pr (Gi0/11)
*Mar 19 19:16:19: timeout timer = 0 (Gi0/11) ④
*Mar 19 19:16:19: Phase set to udld_advertisement from phase udld_link_up in aggresive mode after all neighbors aged out. (Gi0/11)
*Mar 19 19:16:19: UDLD send flush message, flags = 0 (Gi0/11) ⑤
*Mar 19 19:16:19: F (Gi0/11)
*Mar 19 19:16:19: %UDLD-4-UDLD_PORT_DISABLED: UDLD disabled interface Gi0/11, aggressive mode failure detected ⑥
*Mar 19 19:16:19: %PM-4-ERR_DISABLE: udld error detected on Gi0/11, putting Gi0/11 in err-disable state
*Mar 19 19:16:19: Port UDLD set error disabled (Gi0/11)
*Mar 19 19:16:19: Phase set to udld_advertisement after timer_expired. (Gi0/11)
*Mar 19 19:16:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/11, changed state to down
*Mar 19 19:16:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
*Mar 19 19:16:21: %LINK-3-UPDOWN: Interface GigabitEthernet0/11, changed state to down
① 対向機器からUDLD PDU を受信しなくなり、エントリーをテーブルから消去しました。
② Link Up フェイズへ移行しました。
③ 空のEcho TLV を持ったProbe を送信し始めます。 Recommended Timeout フラグとReSynch フラグが立っています。
④ 空のEcho TLV を持ったProbe を8回送信し終わりました。
⑤ Flush を送信しました。
⑥ GigabitEthernet0/11 をErrDisable にしました。
UDLD を究める (1) はじめに
UDLD を究める (2)Bidirectional とUnidirectional
UDLD を究める (3)UDLD とAuto Negotiation
UDLD を究める (4)UDLD の基本動作
UDLD を究める (5)UDLD のパケットフォーマット
UDLD を究める (6)UDLD のタイマー
UDLD を究める (7)Bidirectional State
UDLD を究める (8)Operartional State
UDLD を究める (9)UDLD のアルゴリズム(1)ネイバー関係の確立
UDLD を究める(10)UDLD のアルゴリズム(2)Unidirectional を検知する
UDLD を究める(11)UDLD アグレッシブモード
UDLD を究める(12)UDLD ノーマルモードとアグレッシブモードの互換性
UDLD を究める(13)設定用コマンド
UDLD を究める(14)show コマンド
UDLD を究める(15)UDLD のデバッグ(1)ネイバー関係の確立
UDLD を究める(16)UDLD のデバッグ(2)Unidirectional を検知する
UDLD を究める(17)UDLD のテスト環境を構築する
UDLD を究める(付録) UDLD の状態遷移を時系列で観察する
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