Networking
Cisco 1721 速度慢
我有幾個 Cisco 1721 和一個 WIC-4ESW。我正在執行另一家公司的家用路由器作為我的有線路由器，但決定將其變成無線網橋並使用我額外的思科作為我的路由器。我最近通過我的提供商升級了我的服務計劃，從 8M 降到了 18M。在他們對我的電纜調製解調器做了他們需要的事情之後，我沒有註意到速度上有任何差異。我的提供商在他們的網路上有一個速度測試伺服器來測試，所以我開始測試我的速度，我仍然會在凌晨 2:00 下降 6-8M。
- 我將我的電腦直接連接到電纜調製解調器並執行了幾次測試，並註意到我幾乎每次都下降了大約 18M。我把思科重新打開，回到 6M 下來。試了大約3次。
- 我檢查了 Cisco 上的所有介面，沒有錯誤，也沒有任何異常。然後，我使用完全相同的電纜，讓我的其他公司生產 路由器而不是網橋，並再次執行測試…… 18M 下降了 3 次。
誰能告訴我為什麼我的 Cisco 速度如此之慢？
我什至嘗試從舊式 NAT 切換到 NVI，但這似乎更慢……
我還嘗試更改外部介面的 MAC 地址，認為我的提供商可能正在對我從 DHCP 獲得的源地址執行 QOS。
謝謝，
肖恩
Cisco IOS Software, C1700 Software (C1700-ADVIPSERVICESK9-M), Version 12.4(25d)) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2010 by Cisco Systems, Inc. Compiled Wed 18-Aug-10 04:02 by prod_rel_team ROM: System Bootstrap, Version 12.2(7r)XM2, RELEASE SOFTWARE (fc1) router uptime is 30 minutes System returned to ROM by reload at 06:27:19 UTC Fri Aug 9 2013 System image file is "flash:c1700-advipservicesk9-mz.124-25d.bin" This product contains cryptographic features and is subject to United States and local country laws governing import, export, transfer and use. Delivery of Cisco cryptographic products does not imply third-party authority to import, export, distribute or use encryption. Importers, exporters, distributors and users are responsible for compliance with U.S. and local country laws. By using this product you agree to comply with applicable laws and regulations. If you are unable to comply with U.S. and local laws, return this product immediately. A summary of U.S. laws governing Cisco cryptographic products may be found at: http://www.cisco.com/wwl/export/crypto/tool/stqrg.html If you require further assistance please contact us by sending email to export@cisco.com. Cisco 1721 (MPC860P) processor (revision 0x500) with 118050K/13022K bytes of me. Processor board ID FOC09421G3V (436675680), with hardware revision 0000 MPC860P processor: part number 5, mask 2 1 Ethernet interface 5 FastEthernet interfaces 32K bytes of NVRAM. 32768K bytes of processor board System flash (Read/Write) Configuration register is 0x2102 ------------------------------------------------------------------------------- router#sho inventory NAME: "1721 chassis", DESCR: "1721 chassis, Hw Serial#: 436675680, Hw Revision:" PID: 1721 , VID: 0x500, SN: FOC09421G3V (436675680) NAME: "Chassis Slot", DESCR: "1700 Chassis Slot" PID: 1700 Chassis Slot , VID: , SN: NAME: "C1721 Mainboard", DESCR: "C1721 Mainboard" PID: C1721 Mainboard , VID: 0x500, SN: FOC09421G3V (436675680) NAME: "Daughter card slot:0", DESCR: "1700 DaughterCard Slot" PID: 1700 DaughterCard Slot, VID: , SN: NAME: "WAN Interface Card - 4 Port FE Switch", DESCR: "WAN Interface Card - 4 P" PID: WIC-4ESW= , VID: 1.0, SN: FOC09144DZ1 NAME: "Ethernet0", DESCR: "PQUICC Ethernet" PID: PQUICC Ethernet , VID: , SN: NAME: "FastEthernet1", DESCR: "Fast Ethernet" PID: Fast Ethernet , VID: , SN: NAME: "FastEthernet2", DESCR: "Fast Ethernet" PID: Fast Ethernet , VID: , SN: NAME: "FastEthernet3", DESCR: "Fast Ethernet" PID: Fast Ethernet , VID: , SN: NAME: "FastEthernet4", DESCR: "Fast Ethernet" PID: Fast Ethernet , VID: , SN: NAME: "Daughter card slot:1", DESCR: "1700 DaughterCard Slot" PID: 1700 DaughterCard Slot, VID: , SN: NAME: "FastEthernet0", DESCR: "PQUICC_FEC" PID: PQUICC_FEC , VID: , SN: -------------------------------------------------------------------------------- version 12.4 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption ! hostname router ! boot-start-marker boot-end-marker ! logging buffered 60000 debugging logging console critical enable secret 5 xxx ! aaa new-model ! aaa authentication login default local ! aaa session-id common ip cef ! ip domain name toad-host.com ip auth-proxy max-nodata-conns 3 ip admission max-nodata-conns 3 ! username xxx ! ip ssh version 2 ! interface FastEthernet0 mac-address 0004.4b16.8271 ip address dhcp ip nat outside ip virtual-reassembly speed 100 full-duplex ! interface FastEthernet1 description Inside switchport access vlan 100 ! interface FastEthernet2 shutdown ! interface FastEthernet3 shutdown ! interface FastEthernet4 shutdown ! interface Vlan1 no ip address shutdown ! interface Vlan100 ip address 192.168.1.1 255.255.255.0 ip nat inside ip virtual-reassembly ! ip forward-protocol nd ! ip dns server ! no ip http server no ip http secure-server ip nat inside source list 100 interface FastEthernet0 overload ip nat inside source static tcp 192.168.1.10 22 interface FastEthernet0 22 ! logging trap debugging logging 192.168.1.10 access-list 10 permit 192.168.1.0 0.0.0.255 log access-list 10 deny any log access-list 100 permit ip any any ! control-plane ! line con 0 logging synchronous line aux 0 line vty 0 4 access-class 10 in logging synchronous transport input ssh line vty 5 15 access-class 10 in logging synchronous transport input ssh ! ntp clock-period 17180034 ntp server 192.5.41.41 ntp server 192.5.41.40 end編輯：回應 Paul Rudnitskiy
router#sho ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is 24.49.40.1 to network 0.0.0.0 172.16.0.0/32 is subnetted, 1 subnets S 172.16.100.4 [254/0] via 24.49.40.1, FastEthernet0 24.0.0.0/22 is subnetted, 1 subnets C 24.49.40.0 is directly connected, FastEthernet0 C 192.168.1.0/24 is directly connected, Vlan100 S* 0.0.0.0/0 [254/0] via 24.49.40.1在使用我的提供商的伺服器進行速度測試期間
CPU utilization for five seconds: 34%/32%; one minute: 7%; five minutes: 4% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 39 39132 700 55902 0.65% 0.10% 0.06% 0 Per-minute Jobs 163 1804 336 5369 0.40% 0.98% 0.40% 0 DNS Server Input 9 1512 4110 367 0.24% 0.58% 0.33% 0 ARP Input 162 1908 14331 133 0.16% 0.69% 0.37% 0 DNS Server 48 828 1873 442 0.16% 0.23% 0.14% 0 IP Input 151 60 53 1132 0.08% 0.01% 0.00% 0 Syslog速度測試完成後直接。
CPU utilization for five seconds: 3%/3%; one minute: 8%; five minutes: 5% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 9 1580 4245 372 0.40% 0.51% 0.33% 0 ARP Input 48 840 1895 443 0.16% 0.19% 0.14% 0 IP Input 67 52 753 69 0.08% 0.00% 0.00% 0 IP Background 1 12 12 1000 0.00% 0.00% 0.00% 0 Chunk Manager 2 104 8376 12 0.00% 0.00% 0.00% 0 Load Meter 3 4 412 9 0.00% 0.00% 0.00% 0 Spanning Tree 4 4 1 4000 0.00% 0.00% 0.00% 0 EDDRI_MAIN 5 102004 6382 15983 0.00% 0.22% 0.23% 0 Check heaps
好的，我連接了兩台機器：一台連接到板載 FE 埠，另一台連接到 WIC-4ESW 上的埠。
- 我禁用了主機上的所有防火牆。在兩個介面之間設置不帶 NVI 的 NAT。
- 我執行 iPerf 3 次，平均速度為 9.31 Mbps。
- 我關閉了 NAT，再次嘗試，平均結果差不多。
然後我再次查看了演出版本並註意到了。
1 Ethernet interface 5 FastEthernet interfaces由於板上只有一個 FE，而 WIC-4ESW 有四個，我想知道另一個乙太網介面是從哪裡來的。
經過一番研究，打開板載 FE 和 WIC 之間的任何路由或 WIC 上的 VLAN 間路由都限制為 10Mbps，因為額外的乙太網介面是 CPU 的連結。路由器性能指南中沒有提到，但深埋在 Cisco 網站上的配置指南中。
所以是的…… 1721 將始終被限制（路由）到 CPU 的 10Mbps（全雙工）連結。
根據http://www.cisco.com/web/partners/downloads/765/tools/quickreference/routerperformance.pdf
1721 的峰值吞吐量能力為每秒 12,000 個數據包，數據包最多為 1,500 字節。
這意味著在理想、完美的條件下，1721 的最大速度為 17Mbps。NAT，小數據包大約減半。數據表顯示 CEF 性能為 6.14Mbit/s。
1721 旨在以 T1 速度處理數據。