僅第2層VLAN中的DHCP故障排除 — 無線

monitor capture cap interface TenGigabitEthernet1/0/42 IN     <-- Ingress interface for Edge's S,G Mroute (192.168.0.101, 239.0.17.1)
monitor capture cap interface TenGigabitEthernet1/0/44 OUT    <-- Interface that connects to the DHCP Relay
monitor capture cap match any 
monitor capture cap buffer size 100
monitor capture cap start
monitor capture cap stop

BorderCP-1#show monitor capture cap buffer display-filter "bootp and dhcp.hw.mac_addr==4822.54dc.6a15"
Starting the packet display ........ Press Ctrl + Shift + 6 to exit
  324  16.695022      0.0.0.0 -> 255.255.255.255 DHCP 394 DHCP Discover - Transaction ID 0x824bdf45 <-- 394 is the Lenght of the VXLAN encapsulated packet
  325  10.834141      0.0.0.0 -> 255.255.255.255 DHCP 420 DHCP Discover - Transaction ID 0x168bd882 <-- 420 is the Lenght of the CAPWAP encapsulated packet
  326  16.695053      0.0.0.0 -> 255.255.255.255 DHCP 352 DHCP Discover - Transaction ID 0x824bdf45 <-- 352 is the Lenght of the VXLAN encapsulated packet

Packet 324: VXLAN Encapsulated
BorderCP-1#show monitor capture cap buffer display-filter "frame.number==324" detail | i Internet     
Internet Protocol Version 4, Src: 192.168.0.101, Dst: 239.0.17.1
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255

Packet 326: Plain (dot1Q cannot be captured at egress due to EPC limitations)
BorderCP-1#show monitor capture cap buffer display-filter "frame.number==326" detailed | i Internet        
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255

BorderCP-1#show monitor capture cap buffer display-filter "bootp.type==1 and dhcp.hw.mac_addr==4822.54dc.6a15" detailed | sect Dynamic      
Dynamic Host Configuration Protocol (Discover)
    Message type: Boot Request (1)
    Hardware type: Ethernet (0x01)
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0x00002030
    Seconds elapsed: 3
    Bootp flags: 0x8000, Broadcast flag (Broadcast)
        1... .... .... .... = Broadcast flag: Broadcast   <-- Broadcast Flag set by the Endpoint
        .000 0000 0000 0000 = Reserved flags: 0x0000

提示：bootp.type.==只能用於過濾發現和請求資料包。

DHCP提供和ACK — 廣播 — L2邊框

通訊流 — 僅在第2層廣播DHCP提供和ACK

現在DHCP發現已退出SD-Access交換矩陣，DHCP中繼將插入傳統的DHCP中繼選項（例如GiAddr/GatewayIPAddress），並將資料包作為單播傳輸轉發到DHCP伺服器。在此流程中，SD-Access交換矩陣不附加任何特殊的DHCP選項。

在伺服器收到DHCP發現/請求後，伺服器會執行嵌入的廣播或單播標誌。此標籤指示DHCP中繼代理是否將DHCP提供作為廣播幀或單播幀轉發到下游裝置（我們的邊界）。在本演示中，假設存在廣播場景。

MAC學習和網關註冊

當DHCP中繼傳送DHCP提供或ACK時，L2BN節點必須獲取網關的MAC地址，將其新增到其MAC地址表中，然後到L2/MAC SISF表，最後到VLAN 141的L2LISP資料庫，對映到L2LISP例項8232。

BorderCP-1#show mac address-table interface te1/0/44
          Mac Address Table
-------------------------------------------
Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
31    f87b.2003.7fd5     DYNAMIC     Te1/0/44

BorderCP-1#show vlan id 31
VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
31  L2_Only_Wireless               active    L2LI0:8232, Te1/0/44

BorderCP-1#show device-tracking database mac | i 7fd5|vlan
 MAC                    Interface  vlan       prlvl      state            Time left        Policy           Input_index
 f87b.2003.7fd5         Te1/0/44    31        NO TRUST   MAC-REACHABLE    61 s             LISP-DT-GLEAN-VLAN 64      

BorderCP-1#show lisp ins 8232 dynamic-eid summary | i Name|f87b.2003.7fd5
Dyn-EID Name         Dynamic-EID      Interface     Uptime    Last      Pending
Auto-L2-group-8232  f87b.2003.7fd5  N/A           6d06h     never     0

BorderCP-1#show lisp instance-id 8232 ethernet database f87b.2003.7fd5
LISP ETR MAC Mapping Database for LISP 0 EID-table Vlan  31 (IID 8232), LSBs: 0x1
Entries total 1, no-route 0, inactive 0, do-not-register 0
f87b.2003.7fd5/48,
 dynamic-eid Auto-L2-group-8240, inherited from default locator-set 
rloc_0f43c5d8-f48d-48a5-a5a8-094b87f3a5f7, auto-discover-rlocs
  Uptime: 6d06h, Last-change: 6d06h
  Domain-ID: local
  Service-Insertion: N/A
  Locator        Pri/Wgt  Source     State
 192.168.0.201   10/10   cfg-intf   site-self, reachable
  Map-server     Uptime         ACK  Domain-ID 
  192.168.0.201  6d06h          Yes  0         
  192.168.0.202  6d06h          Yes  0  

如果網關的MAC地址已正確獲知，並且交換矩陣控制平面的ACK標誌已標籤為「Yes」，則此階段視為已完成。

L2泛洪中的DHCP廣播橋接

如果沒有啟用DHCP監聽，DHCP廣播不會受到阻止，而是封裝在組播中，以實現第2層泛洪。反之，如果啟用DHCP監聽，則會阻止DHCP廣播資料包泛洪。

BorderCP-1#show ip dhcp snooping 
Switch DHCP snooping is enabled
Switch DHCP gleaning is disabled
DHCP snooping is configured on following VLANs:
1001
DHCP snooping is operational on following VLANs: 
1001          <-- VLAN31 should not be listed, as DHCP snooping must be disabled in L2 Only pools.
 Proxy bridge is configured on following VLANs:
none
 Proxy bridge is operational on following VLANs:
none

由於L2Border中未啟用DHCP監聽，因此不需要DHCP監聽信任配置。 

在這個階段，兩台裝置都已完成L2LISP ACL驗證。

利用為L2LISP例項配置的廣播底層組和L2Border Loopback0 IP地址來檢驗將該資料包橋接到其他交換矩陣節點的L2泛洪(S，G)條目。請參閱mroute和mfib表以驗證引數，如傳入介面、傳出介面清單和轉發計數器。

BorderCP-1#show ip int loopback 0 | i Internet
  Internet address is 192.168.0.201/32

BorderCP-1#show run | se 8232
interface L2LISP0.8232
instance-id 8232
  remote-rloc-probe on-route-change
  service ethernet
   eid-table vlan 1031
   broadcast-underlay 239.0.17.1

BorderCP-1#show ip mroute 239.0.17.1 192.168.0.201 | be \(
(192.168.0.201, 239.0.17.1), 1w5d/00:02:52, flags: FTA
  Incoming interface: Null0, RPF nbr 0.0.0.0                           <-- Local S,G IIF must be Null0
  Outgoing interface list:
    TenGigabitEthernet1/0/42, Forward/Sparse, 1w3d/00:02:52, flags:    <-- Edge1 Downlink
    TenGigabitEthernet1/0/43, Forward/Sparse, 1w3d/00:02:52, flags:    <-- Edge2 Downlink

BorderCP-1#show ip mfib 239.0.17.1 192.168.0.201 count 
Forwarding Counts: Pkt Count/Pkts per second/Avg Pkt Size/Kilobits per second
Other counts:      Total/RPF failed/Other drops(OIF-null, rate-limit etc)
Default
 13 routes, 6 (*,G)s, 3 (*,G/m)s
Group: 239.0.17.1
  Source: 192.168.0.201,
   SW Forwarding: 1/0/392/0, Other: 1/1/0
   HW Forwarding:   92071/0/102/0, Other: 0/0/0   <-- HW Forwarding counters (First counter = Pkt Count) must increase
  Totals - Source count: 1, Packet count: 92071

提示：如果找不到(S，G)條目或傳出介面清單(OIL)不包含傳出介面(OIF)，則表明底層組播配置或操作有問題。

通過這些驗證，在資料包捕獲方面（與前面步驟相似），我們總結本節內容，因為DHCP提供將以廣播形式轉發到所有交換矩陣邊緣（使用傳出介面清單內容），在本例中是傳出介面TenGig1/0/42和TenGig1/0/43。

DHCP提供和ACK — 廣播 — 邊緣

與上一流完全相同，我們現在檢查交換矩陣邊緣中的L2Border S，G，其中傳入介面指向L2BN，而OIL包含對映到VLAN 1031的L2LISP例項。

Edge-1#show vlan id 1031
VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1031 L2_Only_Wireless                 active    L2LI0:8232, Te1/0/2, Te1/0/17, Te1/0/18, Te1/0/19, Te1/0/20, Ac2, Po1

Edge-1#show ip mroute 239.0.17.1 192.168.0.201 | be \(
(192.168.0.201, 239.0.17.1), 1w3d/00:01:52, flags: JT
  Incoming interface: TenGigabitEthernet1/1/2, RPF nbr 192.168.98.2  <-- IIF Te1/1/2 is the RPF interface for 192.168.0.201 (L2BN RLOC)a
  Outgoing interface list:
    L2LISP0.8232, Forward/Sparse-Dense, 1w3d/00:02:23, flags:

Edge-1#show ip mfib 239.0.17.1 192.168.0.201 count    
Forwarding Counts: Pkt Count/Pkts per second/Avg Pkt Size/Kilobits per second
Other counts:      Total/RPF failed/Other drops(OIF-null, rate-limit etc)
Default
 13 routes, 6 (*,G)s, 3 (*,G/m)s
Group: 239.0.17.1
  Source: 192.168.0.201,
   SW Forwarding: 1/0/96/0, Other: 0/0/0
   HW Forwarding:   76236/0/114/0, Other: 0/0/0  <-- HW Forwarding counters (First counter = Pkt Count) must increase
  Totals - Source count: 1, Packet count: 4

提示：如果未找到(S，G)條目，則表示底層組播配置或操作有問題。如果所需例項的L2LISP未作為OIF存在，則表明L2LISP子介面的操作UP/DOWN狀態或L2LISP介面的IGMP啟用狀態存在問題。

兩台裝置中都已完成L2LISP ACL驗證。

將封包解除封裝並放在與VNI 8232相符的VLAN上後，其廣播性質表示其已泛洪出VLAN1031的所有有線跨距樹狀目錄通訊協定轉送連線埠。 

Edge-1#show spanning-tree vlan 1041 | be Interface
Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Te1/0/2             Desg FWD 20000     128.2    P2p Edge 
Te1/0/17            Desg FWD 2000      128.17   P2p 
Te1/0/18            Back BLK 2000      128.18   P2p 
Te1/0/19            Desg FWD 2000      128.19   P2p 
Te1/0/20            Back BLK 2000      128.20   P2p 

但是，我們希望廣播DHCP提供的介面是與接入點關聯的接入隧道介面。僅因為L2LISP IID 8232上啟用了「泛洪接入隧道」，才可能實現此功能，否則將阻止此資料包轉發到AccessTunnel介面。

Edge-1#show lisp instance-id 8232 ethernet | se Multicast Flood
  Multicast Flood Access-Tunnel:            enabled
    Multicast Address:                      232.255.255.1
    Vlan ID:                                1021

Edge-1#show ip igmp snooping  groups vlan 1021 232.255.255.1
Vlan      Group                    Type        Version     Port List
-----------------------------------------------------------------------
1021      232.255.255.1            igmp        v2          Te1/0/12    <-- AP1 Port

使用組播泛洪組的IGMP監聽條目，DHCP提供和ACK將轉發到AP的物理埠。

DHCP提供和ACK過程始終保持一致。如果未啟用DHCP監聽，則不會在DHCP監聽表中建立任何條目。因此，啟用DHCP的終端的裝置跟蹤條目由收集的ARP資料包生成。由於DHCP監聽已禁用，因此「show platform dhcpsnooping client stats」等命令預計不會顯示任何資料。

Edge-1#show device-tracking database interface Ac2 | be Network
   Network Layer Address                    Link Layer Address     
Interface  vlan       prlvl      age        state      Time left       
ARP 172.16.131.4                             4822.54dc.6a15         Ac2        1031       0005       45s        REACHABLE  207 s try 0    

Edge-1#show ip dhcp snooping  binding vlan 1041
MacAddress          IpAddress        Lease(sec)  Type           VLAN  Interface
------------------  ---------------  ----------  -------------  ----  --------------------
Total number of bindings: 0

DHCP提供和ACK — 單播 — L2邊界

通訊流 — 單播DHCP提供和ACK（僅限第2層）

在此場景略有不同，終端將DHCP廣播標誌設定為unset或「0」。

DHCP中繼不會將DHCP提供/ACK作為廣播傳送，而是作為單播資料包傳送，其目的MAC地址從DHCP負載內的客戶端硬體地址派生。這顯著地修改了SD-Access交換矩陣處理資料包的方式，它使用L2LISP對映快取來轉發流量，而不是第2層泛洪組播封裝方法。

交換矩陣邊界/CP(192.168.0.201)資料包catpure:輸入DHCP提供

BorderCP-1#show monitor capture cap buffer display-filter "bootp.type==1 and 
dhcp.hw.mac_addr==4822.54dc.6a15" detailed | sect Dynamic         
Dynamic Host Configuration Protocol (Discover)
    Message type: Boot Request (1)
    Hardware type: Ethernet (0x01)
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0x00002030
    Seconds elapsed: 0
    Bootp flags: 0x0000, Broadcast flag (Unicast)
        0... .... .... .... = Broadcast flag: Unicast
        .000 0000 0000 0000 = Reserved flags: 0x0000
    Client IP address: 0.0.0.0
    Your (client) IP address: 0.0.0.0
    Next server IP address: 0.0.0.0
    Relay agent IP address: 0.0.0.0
    Client MAC address: 48:22:54:dc:6a:15 (48:22:54:dc:6a:15)

在此場景中，L2泛洪專門用於發現/請求，而提供/ACK則通過L2LISP對映快取轉發，從而簡化了整體操作。根據單播轉發原則，L2邊界向控制平面查詢目的MAC地址。假設在交換矩陣邊緣上成功「MAC學習和WLC通知」，則控制平面已註冊此終端ID(EID)。

BorderCP-1#show lisp instance-id 8232 ethernet server 4822.54dc.6a15       
LISP Site Registration Information
Site name: site_uci
Description: map-server configured from Catalyst Center
Allowed configured locators: any
Requested EID-prefix:
  EID-prefix: 4822.54dc.6a15/48 instance-id 8232 
    First registered:     00:53:30
    Last registered:      00:53:30
    Routing table tag:    0
    Origin:               Dynamic, more specific of any-mac
    Merge active:         No
    Proxy reply:          Yes
    Skip Publication:     No
    Force Withdraw:       No
    TTL:                  1d00h
    State:                complete
    Extranet IID:         Unspecified
    Registration errors:  
      Authentication failures:   0
      Allowed locators mismatch: 0
    ETR 192.168.0.101:51328, last registered 00:53:30, proxy-reply, map-notify
                             TTL 1d00h, no merge, hash-function sha1
                             state complete, no security-capability
                             nonce 0xBB7A4AC0-0x46676094
                             xTR-ID 0xDEF44F0B-0xA801409E-0x29F87978-0xB865BF0D
                             site-ID unspecified
                             Domain-ID 1712573701
                             Multihoming-ID unspecified
                             sourced by reliable transport
      Locator        Local  State      Pri/Wgt  Scope
      192.168.0.101  yes    up          10/10   IPv4 none
    ETR 192.168.254.69:58507, last registered 00:53:30, no proxy-reply, no map-notify    <-- Registered by the Wireless LAN Controller
                              TTL 1d00h, no merge, hash-function sha2
                              state complete, no security-capability
                              nonce 0x00000000-0x00000000
                              xTR-ID N/A
                              site-ID N/A
                              sourced by reliable transport
                              Affinity-id: 0 , 0
                              WLC AP bit: Clear
      Locator        Local  State      Pri/Wgt  Scope
      192.168.0.101  yes    up           0/0    IPv4 none   <-- RLOC of Fabric Edge with the Access Point where the endpoint is connected

 在邊界向控制平面（本地或遠端）查詢後，LISP解析為終端的MAC地址建立對映快取條目。

BorderCP-1#show lisp instance-id 8232 ethernet map-cache 4822.54dc.6a15
LISP MAC Mapping Cache for LISP 0 EID-table Vlan 31 (IID 8232), 1 entries
4822.54dc.6a15/48, uptime: 4d07h, expires: 16:33:09, via map-reply, complete, local-to-site
  Sources: map-reply
  State: complete, last modified: 4d07h, map-source: 192.168.0.206
  Idle, Packets out: 46(0 bytes), counters are not accurate (~ 00:13:12 ago)
  Encapsulating dynamic-EID traffic
  Locator        Uptime    State  Pri/Wgt     Encap-IID
  192.168.0.101  4d07h     up      10/10        -

解決RLOC後，DHCP提供以單播方式封裝，並使用VNI 8240直接傳送到Edge-1(192.168.0.101)。

BorderCP-1#show mac address-table address aaaa.dddd.bbbb
          Mac Address Table
-------------------------------------------
Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
31    4822.54dc.6a15    CP_LEARN    L2LI0

BorderCP-1#show platform software fed switch active matm macTable vlan 141 mac aaaa.dddd.bbbb
VLAN
   MAC                  Type  Seq# EC_Bi  Flags  machandle      
siHandle        riHandle         diHandle   *a_time  *e_time  ports     
                   Con   
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
31    4822.54dc.6a15  0x1000001    0      0    64  0x718eb52c48e8  0x718eb52c8b68  0x718eb44c6c18      0x0            0     1064  RLOC 192.168.0.101 adj_id 1044  No    

BorderCP-1#show ip route 192.168.0.101
Routing entry for 192.168.0.101/32
  Known via "isis", distance 115, metric 20, type level-2
  Redistributing via isis, bgp 65001T
  Advertised by bgp 65001 level-2 route-map FABRIC_RLOC
  Last update from 192.168.98.3 on TenGigabitEthernet1/0/42, 1w3d ago
  Routing Descriptor Blocks:
  * 192.168.98.3, from 192.168.0.101, 1w3d ago, via TenGigabitEthernet1/0/42
      Route metric is 20, traffic share count is 1

使用與前面部分相同的方法，捕獲從DHCP中繼和RLOC輸出介面的輸入流量，以觀察單播到邊緣RLOC的VXLAN封裝。

DHCP提供和ACK — 單播 — 邊緣

邊緣從邊界接收單播DHCP提供/ACK，解封裝流量並查詢其MAC地址表以確定正確的出口埠。與廣播Offer/ACK不同，邊緣節點隨後將僅將資料包轉發到終端所連線的特定接入隧道，而不是將其泛洪到所有埠。

MAC地址表將埠AccessTunnel2標識為與AP1關聯的虛擬埠。

Edge-1#show mac address-table address 4822.54dc.6a15
          Mac Address Table
-------------------------------------------
Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
1031    4822.54dc.6a15    CP_LEARN    Ac2

Edge-1#show interfaces accessTunnel 2 description 
Interface                      Status         Protocol Description
Ac2                            up             up       Radio MAC: dc8c.37ce.58a0, IP: 172.16.1.7

Edge-1#show device-tracking database address 172.16.1.7 | be Network
   Network Layer Address                    Link Layer Address     
Interface  vlan       prlvl      age        state      Time left       
DH4 172.16.1.7                               dc8c.3756.99bc         Te1/0/12   1021       0024       6s         REACHABLE  241 s try 0(86353 s)

Edge-1#show cdp neighbors tenGigabitEthernet 1/0/12 | be Device
Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID
AP1              Ten 1/0/12        119              R T   AIR-AP480 Gig 0

DHCP提供和ACK過程始終保持一致。如果未啟用DHCP監聽，則不會在DHCP監聽表中建立任何條目。因此，啟用DHCP的終端的裝置跟蹤條目由收集的ARP資料包生成，而不是DHCP。由於DHCP監聽已禁用，因此「show platform dhcpsnooping client stats」等命令也會不顯示任何資料。

Edge-1#show device-tracking database interface te1/0/2 | be Network
   Network Layer Address                    Link Layer Address     
Interface  vlan       prlvl      age        state      Time left       
ARP 172.16.141.1                             aaaa.dddd.bbbb         Te1/0/2    1041       0005       45s        REACHABLE  207 s try 0     
Edge-1#show ip dhcp snooping  binding vlan 1041
MacAddress          IpAddress        Lease(sec)  Type           VLAN  Interface
------------------  ---------------  ----------  -------------  ----  --------------------
Total number of bindings: 0

必須注意的是，SD-Access交換矩陣不影響單播或廣播標誌的使用，因為這只是端點行為。雖然此功能可能被DHCP中繼或DHCP伺服器本身所覆蓋，但兩種機制對於在L2 Only環境中無縫DHCP操作都至關重要：使用廣播提供/ACK的底層組播進行第2層泛洪，並在控制平面中為單播提供/ACK進行正確的端點註冊。

DHCP交易 — 無線驗證

在WLC上，DHCP交易是透過RA-Trace進行監控。

WLC#debug wireless mac 48:22:54:DC:6A:15 to-file bootflash:client6a15 
    RA tracing start event,
       conditioned on MAC address: 48:22:54:dc:6a:15
       Trace condition will be automatically stopped in 1800 seconds.
       Execute 'no debug wireless mac 48:22:54:dc:6a:15' to manually stop RA tracing on this condition.

WLC#no debug wireless mac 48:22:54:dc:6a:15
    RA tracing stop event,
       conditioned on MAC address: 48:22:54:dc:6a:15

WLC#more flash:client6a15 | i DHCP
2025/08/11 06:13:48.600929726 {wncd_x_R0-0}{1}: [sisf-packet] [15981]: (info): RX: DHCPv4 from interface capwap_90000006 on vlan 1 Src MAC: 4822.54dc.6a15 Dst MAC: ffff.ffff.ffff src_ip: 0.0.0.0, dst_ip: 255.255.255.255, BOOTPREQUEST, SISF_DHCPDISCOVER, giaddr: 0.0.0.0, yiaddr: 0.0.0.0, CMAC: 4822.54dc.6a15 
2025/08/11 06:13:50.606037404 {wncd_x_R0-0}{1}: [sisf-packet] [15981]: (info): RX: DHCPv4 from interface capwap_90000006 on vlan 1 Src MAC: f87b.2003.7fd5 Dst MAC: 4822.54dc.6a15 src_ip: 172.16.131.254, dst_ip: 172.16.131.4, BOOTPREPLY, SISF_DHCPOFFER, giaddr: 172.16.131.254, yiaddr: 172.16.131.4, CMAC: 4822.54dc.6a15 
2025/08/11 06:13:50.609855406 {wncd_x_R0-0}{1}: [sisf-packet] [15981]: (info): RX: DHCPv4 from interface capwap_90000006 on vlan 1 Src MAC: 4822.54dc.6a15 Dst MAC: ffff.ffff.ffff src_ip: 0.0.0.0, dst_ip: 255.255.255.255, BOOTPREQUEST, SISF_DHCPREQUEST, giaddr: 0.0.0.0, yiaddr: 0.0.0.0, CMAC: 4822.54dc.6a15 
2025/08/11 06:13:50.613054692 {wncd_x_R0-0}{1}: [sisf-packet] [15981]: (info): RX: DHCPv4 from interface capwap_90000006 on vlan 1 Src MAC: f87b.2003.7fd5 Dst MAC: 4822.54dc.6a15 src_ip: 172.16.131.254, dst_ip: 172.16.131.4, BOOTPREPLY, SISF_DHCPACK, giaddr: 172.16.131.254, yiaddr: 172.16.131.4, CMAC: 4822.54dc.6a15 

在事務結束時，終端會新增到無線LAN控制器上的裝置跟蹤資料庫。

WLC#show wireless device-tracking database mac 4822.54dc.6a15 
  MAC             VLAN  IF-HDL      IP                                          ZONE-ID/VRF-NAME
  --------------------------------------------------------------------------------------------------
  4822.54dc.6a15  1     0x90000006  172.16.131.4                                0x00000000
                                    fe80::b070:b7e1:cc52:69ed                   0x80000001

整個DHCP事務在接入點上調試。

AP1#debug client 48:22:54:DC:6A:15
AP1#term mon

AP1#
Aug 11 05:37:47 AP1 kernel: [*08/11/2025 05:37:47.3530] [1754890667:353058] [AP1] [48:22:54:dc:6a:15] < wifi0> [U:W] DHCP_DISCOVER : TransId 0x76281006
Aug 11 05:37:47 AP1 kernel: [*08/11/2025 05:37:47.3531] chatter: dhcp_req_local_sw_nonat: 1754890667.353086: 0.0.0.0.68 > 255.255.255.255.67: udp 310
Aug 11 05:37:47 AP1 kernel: [*08/11/2025 05:37:47.3533] chatter: dhcp_from_inet: 1754890667.353287600: 0.0.0.0.68 > 255.255.255.255.67: udp 310
Aug 11 05:37:47 AP1 kernel: [*08/11/2025 05:37:47.3533] chatter: dhcp_reply_nonat: 1754890667.353287600: 0.0.0.0.68 > 255.255.255.255.67: udp 310
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3587] chatter: dhcp_from_inet: 1754890669.358709760: 172.16.131.254.67 > 172.16.131.4.68: udp 309
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3588] chatter: dhcp_reply_nonat: 1754890669.358709760: 172.16.131.254.67 > 172.16.131.4.68: udp 309
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3589] [1754890669:358910] [AP1] [48:22:54:dc:6a:15]  [D:W] DHCP_OFFER : TransId 0x76281006 tag:534
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3671] [1754890669:367110] [AP1] [48:22:54:dc:6a:15] < wifi0> [U:W] DHCP_REQUEST : TransId 0x76281006
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3671] chatter: dhcp_req_local_sw_nonat: 1754890669.367134760: 0.0.0.0.68 > 255.255.255.255.67: udp 336
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3709] [1754890669:370945] [AP1] [48:22:54:dc:6a:15]  [D:W] DHCP_ACK : TransId 0x76281006 tag:536
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3733] [1754890669:373312] [AP1] [48:22:54:dc:6a:15] < wifi0> [D:A] DHCP_OFFER : TransId 0x76281006 [Tx Success] tag:534
Aug 11 05:37:49 AP1 kernel: [*08/11/2025 05:37:49.3983] [1754890669:398318] [AP1] [48:22:54:dc:6a:15] < wifi0> [D:A] DHCP_ACK : TransId 0x76281006 [Tx Success] tag:53

* U:W = Uplink Packet from Client to Wireless Driver
* D:W = Downlink Packet from Client to Click Module
* D:A = Downlink Packet from Client sent over the air