ACI L3Out — 子網0.0.0.0/0和系統PcTag 15故障排除
目錄
簡介
本文檔介紹在L3Out EPG中定義0.0.0.0/0子網的PcTag派生。
背景資訊
ACI Contract Guide的「L3Out EPG with 0.0.0.0/0 subnet」部分將0.0.0.0/0與「External Subnets for the External EPG」範圍流量分類總結為：
- 源自L3Out且是匹配到已配置0.0.0.0/0子網的最長字首的流量將分配給VRF PcTag的源類ID（類）。
- 目的地為與已配置的0.0.0.0/0子網匹配的最長字首的L3Out EPG的流量將目標類ID(dclass)分配為15，即系統PcTag。
ACI L3Out白皮書的「An exception for 0.0.0.0/0 with External Subnets for the External EPG」部分包含一條警告：
"。..儘管不建議這樣做，但您可以在同一VRF中的多個L3Out EPG中使用「外部EPG的子網」配置0.0.0.0/0。 允許此配置時，會發生意外的合約部署……」
本文深入探討這種意想不到的合約部署。
設定
拓撲圖
配置要點
- 枝葉節點301和303是邊界枝葉節點
- 枝葉節點302是非邊界枝葉
- 邊界枝葉301上的L3Out-1-EEPG有一個0.0.0.0/0子網，其中包含「外部EPG的外部子網」
- L3Out-1-EEPG提供合約
- 非邊界枝葉302上的EPG使用相同的合約
驗證
實施「輸入」策略的VRF
非邊界枝葉分割槽規則
如「背景資訊」一節中突出顯示的，發往此L3Out後網路(已配置0.0.0.0/0子網中最長字首匹配項為15的流量將獲得目標類(pcTag)。
這是VRF "v1"(網段ID 2129920)的非邊界枝葉302上的分割槽規則表：
Leaf-302# show zoning-rule scope 2129920 +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | 4107 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4106 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4105 | 0 | 49155 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | | 4108 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4112 | 16386 | 49156 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4111 | 49156 | 15 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+
由於L3Out-1-EEPG和EPG(49156)之間的合約，安裝了兩個規則：
- 規則4112適用於來源為L3Out EPG且目的地為0.0.0.0/0 LPM的外部流量。
- 流量使用VRF PcTag(16386)和EPG(49156)的類別進行分類。
- 規則4111適用於來源為EPG且目的地為0.0.0.0/0 LPM的L3Out EPG的流量。
- 流量使用EPG類(49156)和System PcTag 15類分類
邊界枝葉分割槽 — 規則
由於VRF策略實施設定為「輸入」（預設值），邊界枝葉節點301沒有與非邊界枝葉節點302相同的分割槽規則。 這些型別的流的策略應應用於非邊界枝葉節點。
Leaf-301# show zoning-rule scope 2129920 +---------+--------+--------+----------+---------+---------+---------+------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+---------+---------+---------+------+----------+----------------------+ | 4105 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4107 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4106 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4108 | 0 | 16387 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | +---------+--------+--------+----------+---------+---------+---------+------+----------+----------------------+
*No entry for 16386 to 49156 , or 49156 to 15*
EPG到L3Out ELAM
從EPG端點192.168.1.1 ping L3Out-1-EEPG之後的IP成功：
Host# ping 10.1.1.1 count 10000 int 1 PING 10.1.1.1 (10.1.1.1): 56 data bytes 64 bytes from 10.1.1.1: icmp_seq=0 ttl=252 time=1.063 ms 64 bytes from 10.1.1.1: icmp_seq=1 ttl=252 time=0.92 ms 64 bytes from 10.1.1.1: icmp_seq=2 ttl=252 time=0.963 ms
非邊界枝葉302（EPG網關）上的EPG到L3Out流量的ELAM確認：
- 封包具有預期的來源和目的地IP:源IP:192.168.1.1，目的IP:10.1.1.1
- 源類（類）是EPG PcTag類49156
- 目的地類別(dclass)為系統PcTag 15，因為10.1.1.0/24最長字首匹配L3Out-1-EEPG上的0.0.0.0/0子網
- 在此節點302（非邊界枝葉節點）上應用了策略。
Leaf-302# ereport
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
...snip...
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L2 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
Destination MAC : 0022.BDF8.19FF
Source MAC : AAAA.AAAA.2222
802.1Q tag is valid : yes( 0x1 )
CoS : 0( 0x0 )
Access Encap VLAN : 192( 0xC0 )
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
...
IP Protocol Number : ICMP
IP CheckSum : 63781( 0xF925 )
Destination IP : 10.1.1.1
Source IP : 192.168.1.1
...
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 2048( 0x800 )
L4 Dst Port : 43014( 0xA806 )
sclass (src pcTag) : 49156( 0xC004 )
dclass (dst pcTag) : 15( 0xF )
src pcTag is from local table : yes
...
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : yes
Contract Hit : yes
Contract Aclqos Stats Index : 81875
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81875" )
可以輸入ereport提供的命令，以便進一步驗證所命中的Zoning-Rule:
module-1(DBG-elam-insel6)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81875"
===========================================
Rule ID: 4111 Scope 6 Src EPG: 49156 Dst EPG: 15 Filter 65535
unit_id: 0
=== Region priority: 2462 (rule prio: 9 entry: 158)===
sw_index = 46 | hw_index = 45 | stats_idx = 81875
Curr TCAM resource:
=============================
=== SDK Info ===
Result/Stats Idx: 81875
L3Out到EPG ELAM
返回流將策略應用於非邊界枝葉節點302。當VRF策略實施設定為「輸入」時，這是預期情況。
Leaf-302# ereport
... ------------------------------------------------------------------------------------------------------------------------------------------------------ Inner L3 Header ------------------------------------------------------------------------------------------------------------------------------------------------------ L3 Type : IPv4 DSCP : 0 Don't Fragment Bit : 0x0 TTL : 254 IP Protocol Number : ICMP Destination IP : 192.168.1.1 Source IP : 10.1.1.1 ====================================================================================================================================================== Contract Lookup ( FPC ) ====================================================================================================================================================== ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Lookup Key ------------------------------------------------------------------------------------------------------------------------------------------------------ IP Protocol : ICMP( 0x1 ) L4 Src Port : 0( 0x0 ) L4 Dst Port : 60691( 0xED13 ) sclass (src pcTag) : 16386( 0x4002 ) dclass (dst pcTag) : 49156( 0xC004 ) src pcTag is from local table : no derived from group-id in iVxLAN header of incoming packet Unknown Unicast / Flood Packet : no If yes, Contract is not applied here because it is flooded ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Result ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Drop : no Contract Logging : no Contract Applied : yes Contract Hit : yes Contract Aclqos Stats Index : 81874 ( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874" )
進一步驗證：
module-1(DBG-elam-insel14)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874"
===========================================
Rule ID: 4112 Scope 6 Src EPG: 16386 Dst EPG: 49156 Filter 65535
unit_id: 0
=== Region priority: 2462 (rule prio: 9 entry: 158)===
sw_index = 47 | hw_index = 46 | stats_idx = 81874
Curr TCAM resource:
=============================
=== SDK Info ===
Result/Stats Idx: 81874
module-1(DBG-elam-insel14)#
實施「出口」策略的VRF
非邊界枝葉分割槽規則
當VRF策略實施設定為「輸出」時，L3Out的合約規則將部署在邊界枝葉節點和非邊界枝葉節點上。因此，與「輸入」實施相比，此配置會消耗額外的TCAM空間。此組態不是預設值，若使用，必須慎重考慮。
非邊界枝葉節點302有兩個分割槽規則，每個流方向性一個：
Leaf-302# show zoning-rule scope 2129920 +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | 4107 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4106 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4105 | 0 | 49155 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | | 4108 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4112 | 16386 | 49156 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4111 | 49156 | 15 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+
邊界枝葉分割槽 — 規則
通過「出口」策略實施，Border Leaf Node 301還有另外兩個分割槽規則：
Leaf-301# show zoning-rule scope 2129920 +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | 4105 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4107 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4106 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4108 | 0 | 16387 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | | 4109 | 16386 | 49156 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4110 | 49156 | 15 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+
EPG到L3Out ELAM
從終端192.168.1.1 ping L3Out背後的網路成功：
Host# ping 10.1.1.1 count 10000 int 1 PING 10.1.1.1 (10.1.1.1): 56 data bytes 64 bytes from 10.1.1.1: icmp_seq=0 ttl=252 time=1.319 ms 64 bytes from 10.1.1.1: icmp_seq=1 ttl=252 time=0.962 ms 64 bytes from 10.1.1.1: icmp_seq=2 ttl=252 time=0.958 ms 64 bytes from 10.1.1.1: icmp_seq=3 ttl=252 time=1.093 ms
非邊界枝葉節點302上的ELAM表示未在此枝葉上應用策略。此外，它還選擇了System PcTag 1類，以允許流命中流中的下一個葉節點：
Leaf-302# ereport
======================================================================================================================================================
Captured Packet
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
...
IP Protocol Number : ICMP
IP CheckSum : 26943( 0x693F )
Destination IP : 10.1.1.1
Source IP : 192.168.1.1
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 2048( 0x800 )
L4 Dst Port : 27360( 0x6AE0 )
sclass (src pcTag) : 49156( 0xC004 )
dclass (dst pcTag) : 1( 0x1 )
...
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : no
Contract Hit : yes
Contract Aclqos Stats Index : 81903
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81903" )
邊界枝葉節點301上的ELAM指示該節點上應用了策略。它還選擇了系統PcTag 15類。這表示0.0.0.0/0 L3Out子網條目上匹配的最長字首：
Leaf-301# ereport
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
...
IP Protocol Number : ICMP
Destination IP : 10.1.1.1
Source IP : 192.168.1.1
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 2048( 0x800 )
L4 Dst Port : 40498( 0x9E32 )
sclass (src pcTag) : 49156( 0xC004 )
dclass (dst pcTag) : 15( 0xF )
src pcTag is from local table : no
derived from group-id in iVxLAN header of incoming packet
Unknown Unicast / Flood Packet : no
If yes, Contract is not applied here because it is flooded
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : yes
Contract Hit : yes
Contract Aclqos Stats Index : 81874
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874" )
...
module-1(DBG-elam-insel14)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874"
===========================================
Rule ID: 4110 Scope 6 Src EPG: 49156 Dst EPG: 15 Filter 65535
unit_id: 0
=== Region priority: 2462 (rule prio: 9 entry: 158)===
sw_index = 47 | hw_index = 46 | stats_idx = 81874
Curr TCAM resource:
=============================
=== SDK Info ===
Result/Stats Idx: 81874
L3Out到EPG ELAM
此設定中的返回流存在警告：
- 邊界枝葉節點301沒有針對192.168.1.1的終端學習。
Leaf-301# show endpoint ip 192.168.1.1
Legend:
S - static s - arp L - local O - peer-attached
V - vpc-attached a - local-aged p - peer-aged M - span
B - bounce H - vtep R - peer-attached-rl D - bounce-to-proxy
E - shared-service m - svc-mgr
+-----------------------------------+---------------+-----------------+--------------+-------------+
VLAN/ Encap MAC Address MAC Info/ Interface
Domain VLAN IP Address IP Info
+-----------------------------------+---------------+-----------------+--------------+-------------+
...empty...
因此，未針對此流在邊界枝葉節點301上應用策略，必須隱式允許它到達下一個枝葉：
Leaf-301# ereport
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
...
IP Protocol Number : ICMP
IP CheckSum : 25157( 0x6245 )
Destination IP : 192.168.1.1
Source IP : 10.1.1.1
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 0( 0x0 )
L4 Dst Port : 33570( 0x8322 )
sclass (src pcTag) : 16386( 0x4002 )
dclass (dst pcTag) : 1( 0x1 )
src pcTag is from local table : yes
derived from a local table on this node by the lookup of src IP or MAC
Unknown Unicast / Flood Packet : no
If yes, Contract is not applied here because it is flooded
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : no
Contract Hit : yes
Contract Aclqos Stats Index : 81903
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81903" )
相反，策略應用於非邊界枝葉節點302:
Leaf-302# ereport
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
...
IP Protocol Number : ICMP
Destination IP : 192.168.1.1
Source IP : 10.1.1.1
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 0( 0x0 )
L4 Dst Port : 61057( 0xEE81 )
sclass (src pcTag) : 16386( 0x4002 )
dclass (dst pcTag) : 49156( 0xC004 )
src pcTag is from local table : no
derived from group-id in iVxLAN header of incoming packet
Unknown Unicast / Flood Packet : no
If yes, Contract is not applied here because it is flooded
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : yes
Contract Hit : yes
Contract Aclqos Stats Index : 81874
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874" )
...
module-1(DBG-elam-insel14)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81874"
===========================================
Rule ID: 4112 Scope 6 Src EPG: 16386 Dst EPG: 49156 Filter 65535
unit_id: 0
=== Region priority: 2462 (rule prio: 9 entry: 158)===
sw_index = 47 | hw_index = 46 | stats_idx = 81874
Curr TCAM resource:
=============================
=== SDK Info ===
Result/Stats Idx: 81874
如果邊界枝葉節點301具有終端獲知192.168.1.1，則在該節點上應用策略。
疑難排解
場景 — 意外允許
0.0.0/0如果部署在同一VRF中配置了多個L3Outs，且子網中配置了「外部EPG的外部子網」，則會允許流量意外傳遞到外部目標。
為此，請在L3Out-2-EEPG下新增0.0.0.0/0子網，該子網與L3Out-1-EEPG位於同一VRF中。
在L3Out-2-EEPG上沒有合約，因此我們預計預設情況下所有流量都會被丟棄：
但是，從EPG端點192.168.1.1 ping L3Out-2-EEPG後的目的地10.2.2.2成功。這是意外的！
Host# ping 10.2.2.2 PING 10.2.2.2 (10.2.2.2): 56 data bytes 64 bytes from 10.2.2.2: icmp_seq=0 ttl=252 time=0.881 ms 64 bytes from 10.2.2.2: icmp_seq=1 ttl=252 time=0.801 ms 64 bytes from 10.2.2.2: icmp_seq=2 ttl=252 time=0.877 ms 64 bytes from 10.2.2.2: icmp_seq=3 ttl=252 time=0.827 ms
轉發路由和policy-mgr字首都顯示此VRF中目的地為10.2.2.2的流量被分配系統PcTag 15
Leaf-302# vsh_lc -c "show forward route 10.2.2.2 platform vrf tn1:v1" ... Policy Prefix 0.0.0.0/0 SDK Information: vrf: 7(0x7), routed_if: 0x0 epc_class: 15(0xf) ... Leaf-302# vsh -c "show system internal policy-mgr prefix" Requested prefix data Vrf-Vni VRF-Id Table-Id Table-State VRF-Name Addr Class Shared Remote Complete Svc_ena ======= ====== =========== ======= ============================ ================================= ====== ====== ====== ======== ======== ... 2129920 7 0x7 Up tn1:v1 0.0.0.0/0 15 False False False False 2129920 7 0x80000007 Up tn1:v1 ::/0 15 False False False False Leaf-302#
非邊界枝葉節點302上的ELAM驗證使用系統PcTag 15類對流量進行分類。
Leaf-302# ereport
====================================================================================================================================================== Captured Packet ====================================================================================================================================================== ------------------------------------------------------------------------------------------------------------------------------------------------------ Outer L3 Header ------------------------------------------------------------------------------------------------------------------------------------------------------ ... IP Protocol Number : ICMP IP CheckSum : 14444( 0x386C ) Destination IP : 10.2.2.2 Source IP : 192.168.1.1 ====================================================================================================================================================== Contract Lookup ( FPC ) ====================================================================================================================================================== ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Lookup Key ------------------------------------------------------------------------------------------------------------------------------------------------------ IP Protocol : ICMP( 0x1 ) L4 Src Port : 2048( 0x800 ) L4 Dst Port : 33134( 0x816E ) sclass (src pcTag) : 49156( 0xC004 ) dclass (dst pcTag) : 15( 0xF ) src pcTag is from local table : yes derived from a local table on this node by the lookup of src IP or MAC Unknown Unicast / Flood Packet : no If yes, Contract is not applied here because it is flooded ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Result ------------------------------------------------------------------------------------------------------------------------------------------------------ Contract Drop : no Contract Logging : no Contract Applied : yes Contract Hit : yes Contract Aclqos Stats Index : 81875 ( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81875" ) ...
module-1(DBG-elam-insel6)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81875" =========================================== Rule ID: 4111 Scope 6 Src EPG: 49156 Dst EPG: 15 Filter 65535 unit_id: 0 === Region priority: 2462 (rule prio: 9 entry: 158)=== sw_index = 46 | hw_index = 45 | stats_idx = 81875 Curr TCAM resource: ============================= === SDK Info === Result/Stats Idx: 81875
VRF "v1"的分割槽規則未顯示EPG和L3Out-2的任何新條目：
Leaf-302# show zoning-rule scope 2129920 +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ | 4107 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4106 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4105 | 0 | 49155 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | | 4108 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4112 | 16386 | 49156 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4111 | 49156 | 15 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | +---------+--------+--------+----------+---------+---------+---------+------------------+----------+----------------------+ Leaf-302#
由於L3Out-2-EEPG僅配置了0.0.0.0/0子網，因此所有發往它的流量都使用System PcTag 15分類進行分類。
Zoning-Rules ID 4111和4112被程式設計為L3Out-1-EEPG具有0.0.0.0/0子網並提供EPG使用的合約。
由於此配置，意外地允許到L3Out-2-EEPG的流！
解決方案 — 無意允許
要防止此行為，請執行以下操作：
- 強烈建議每個VRF僅對一個L3Out EPG使用0.0.0.0/0子網
- 如有可能，在同一VRF中的其他L3Out使用特定子網。這允許流量將唯一的L3Out PcTag值提取為其類。
應用這些更改以緩解意外允許：
- 在L3Out-2-EEPG上，將0.0.0.0/0子網替換為10.2.2.0/24子網
- 在L3Out-2-EEPG上，提供合約
- 在EPG上，使用相同的合約
完成後，在非邊界枝葉節點302上觀察這些更改：
- 對於10.2.2.0/24，有一個更具體的policy-mgr字首與L3Out-2-EEPG PcTag連線關32771
- 有一個Zoning-Rules ID 4109條目
- 此條目允許從EPG PcTag到491563Out-2-EEPG PcTag的流32771
- 有一個Zoning-Rules ID 4110條目
- 此條目允許從L3Out-2-EEPG PcTag到EPG 32771的流49156
更新的轉發路由和policy-mgr字首，其中顯示10.2.2.2分配了32771的L3Out-2-EEPG PgTag:
Leaf-302# vsh_lc -c "show forward route 10.2.2.2 platform vrf tn1:v1" ... Policy Prefix 10.2.2.0/24 ... SDK Information: vrf: 7(0x7), routed_if: 0x0 epc_class: 32771(0x8003) attributes: SUP_CP DST_POL_IC SRC_POL_IC
Leaf-302# vsh -c "show system internal policy-mgr prefix" Requested prefix data Vrf-Vni VRF-Id Table-Id Table-State VRF-Name Addr Class Shared Remote Complete Svc_ena ======= ====== =========== ======= ============================ ================================= ====== ====== ====== ======== ======== ... 2129920 7 0x7 Up tn1:v1 0.0.0.0/0 15 False False False False 2129920 7 0x80000007 Up tn1:v1 ::/0 15 False False False False 2129920 7 0x7 Up tn1:v1 10.2.2.0/24 32771 False True False False
Leaf-302# show zoning-rule scope 2129920 +---------+--------+--------+----------+----------------+---------+---------+------------------+----------+----------------------+ | Rule ID | SrcEPG | DstEPG | FilterID | Dir | operSt | Scope | Name | Action | Priority | +---------+--------+--------+----------+----------------+---------+---------+------------------+----------+----------------------+ | 4107 | 0 | 0 | implarp | uni-dir | enabled | 2129920 | | permit | any_any_filter(17) | | 4106 | 0 | 0 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_any_any(21) | | 4105 | 0 | 49155 | implicit | uni-dir | enabled | 2129920 | | permit | any_dest_any(16) | | 4108 | 0 | 15 | implicit | uni-dir | enabled | 2129920 | | deny,log | any_vrf_any_deny(22) | | 4112 | 16386 | 49156 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4111 | 49156 | 15 | default | uni-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4109 | 49156 | 32771 | default | bi-dir | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | | 4110 | 32771 | 49156 | default | uni-dir-ignore | enabled | 2129920 | tn1:EPG_to_L3Out | permit | src_dst_any(9) | +---------+--------+--------+----------+----------------+---------+---------+------------------+----------+----------------------+
從EPG主機ping L3Out-2-EEPG後的外部目標成功：
Host# ping 10.2.2.2 PING 10.2.2.2 (10.2.2.2): 56 data bytes
64 bytes from 10.2.2.2: icmp_seq=0 ttl=252 time=0.854 ms
64 bytes from 10.2.2.2: icmp_seq=1 ttl=252 time=0.669 ms
64 bytes from 10.2.2.2: icmp_seq=2 ttl=252 time=0.716 ms
64 bytes from 10.2.2.2: icmp_seq=3 ttl=252 time=0.669 ms
64 bytes from 10.2.2.2: icmp_seq=4 ttl=252 time=0.666 ms
非邊界枝葉節點302上icmp請求的ELAM指示該類現在為32771 - L3Out-2-EEPG的PcTag。
Leaf-302# ereport
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
...
IP Protocol Number : ICMP
IP CheckSum : 4095( 0xFFF )
Destination IP : 10.2.2.2
Source IP : 192.168.1.1
======================================================================================================================================================
Contract Lookup ( FPC )
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Lookup Key
------------------------------------------------------------------------------------------------------------------------------------------------------
IP Protocol : ICMP( 0x1 )
L4 Src Port : 2048( 0x800 )
L4 Dst Port : 49837( 0xC2AD )
sclass (src pcTag) : 49156( 0xC004 )
dclass (dst pcTag) : 32771( 0x8003 )
src pcTag is from local table : yes
derived from a local table on this node by the lookup of src IP or MAC
Unknown Unicast / Flood Packet : no
If yes, Contract is not applied here because it is flooded
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Result
------------------------------------------------------------------------------------------------------------------------------------------------------
Contract Drop : no
Contract Logging : no
Contract Applied : yes
Contract Hit : yes
Contract Aclqos Stats Index : 81873
( show sys int aclqos zoning-rules | grep -B 9 "Idx: 81873" )
...
ereport提供的aclqos命令顯示此流命中了一個新的分割槽規則，特別是規則ID 4109:
module-1(DBG-elam-insel6)# show sys int aclqos zoning-rules | grep -B 9 "Idx: 81873"
===========================================
Rule ID: 4109 Scope 6 Src EPG: 49156 Dst EPG: 32771 Filter 65535
unit_id: 0
=== Region priority: 2462 (rule prio: 9 entry: 158)===
sw_index = 48 | hw_index = 47 | stats_idx = 81873
Curr TCAM resource:
=============================
=== SDK Info ===
Result/Stats Idx: 81873
修訂記錄
| 修訂 | 發佈日期 | 意見 |
|---|---|---|
2.0 |
01-Sep-2022 |
已新增轉發路由和policy-mgr字首輸出 |
1.0 |
30-Aug-2022 |
初始版本 |
意見