我有一台 Juniper QFX5100，配置基本与原厂配置相同。我在它们之间使用聚合接口。当我在服务器之间使用交叉连接时，一切都运行正常，我获得了 10GB 的带宽。当我通过 Juniper QFX5100 时，我几乎得不到任何带宽（iperf 测量结果为几 kb，scp 甚至没有变化）。我在日志中找不到任何可以说明原因的内容。
以下是 QFX 配置。ServerA 连接到 XE-0/0/46，ServerB 连接到 XE-0/0/42。
set version 13.2X51-D10.6
set system host-name sw1
set system time-zone America/New_York
set system name-server 8.8.8.8
set system name-server 4.2.2.2
set system services ssh protocol-version v2
set system services netconf ssh
set system services web-management http port 1981
set system services dhcp traceoptions file dhcp_logfile
set system services dhcp traceoptions level all
set system services dhcp traceoptions flag all
set system syslog user * any emergency
set system syslog host 1.1.1.1 any any
set system syslog file messages any notice
set system syslog file messages authorization info
set system syslog file interactive-commands interactive-commands any
set system ntp server 74.207.249.60
set system ntp server 65.55.21.21
set system ntp server 74.118.152.85
set system ntp server 65.55.21.13
set chassis aggregated-devices ethernet device-count 20
set chassis auto-image-upgrade
set interfaces ge-0/0/0 description COGENT_UPLINK_1400A-TCURVE-ST01-Gi3-P14
set interfaces ge-0/0/0 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members FW-UNTRUST
set interfaces ge-0/0/1 description COGENT_UPLINK_1400A-TCURVE-ST02-Gi3-P14
set interfaces ge-0/0/1 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/1 unit 0 family ethernet-switching vlan members FW-UNTRUST
set interfaces ge-0/0/2 description CONNECTED_TO_FW1-xe-0/0/2
set interfaces ge-0/0/2 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/2 unit 0 family ethernet-switching vlan members FW-UNTRUST
set interfaces ge-0/0/3 description CONNECTED_TO_FW1-xe-0/0/3
set interfaces ge-0/0/3 unit 0 family ethernet-switching interface-mode trunk
set interfaces ge-0/0/3 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/3 unit 0 family ethernet-switching vlan members devlan
set interfaces ge-0/0/4 description CONNECTED_TO_TPLINK_PORT1_FOR_APC_DEVICES
set interfaces ge-0/0/4 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/4 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/26 description vi_RAC
set interfaces ge-0/0/26 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/26 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/28 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/28 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/29 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/29 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces xe-0/0/30 unit 0 family ethernet-switching interface-mode access
set interfaces xe-0/0/30 unit 0 family ethernet-switching vlan members devlan
set interfaces xe-0/0/31 unit 0 family ethernet-switching interface-mode access
set interfaces xe-0/0/31 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces xe-0/0/34 ether-options 802.3ad ae1
set interfaces xe-0/0/35 ether-options 802.3ad ae1
set interfaces ge-0/0/37 description RAC_web1
set interfaces ge-0/0/37 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/37 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces xe-0/0/38 description CONNECTED_TO_web1_p4p1
set interfaces xe-0/0/38 ether-options 802.3ad ae0
set interfaces xe-0/0/39 description CONNECTED_TO_web1_p4p2
set interfaces xe-0/0/39 ether-options 802.3ad ae0
set interfaces ge-0/0/40 description codd-a02-em3
set interfaces ge-0/0/40 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/40 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/41 description codd-a02_iDRAC
set interfaces ge-0/0/41 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/41 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces xe-0/0/42 description codd-a02-em1
set interfaces xe-0/0/42 ether-options 802.3ad ae2
set interfaces xe-0/0/43 description codd-a02-em2
set interfaces xe-0/0/43 ether-options 802.3ad ae2
set interfaces ge-0/0/44 description codd-b01-em3
set interfaces ge-0/0/44 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/44 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ge-0/0/45 description codd-b01-DRAC
set interfaces ge-0/0/45 unit 0 family ethernet-switching interface-mode access
set interfaces ge-0/0/45 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces xe-0/0/46 description codd-b01-em1
set interfaces xe-0/0/46 ether-options 802.3ad ae3
set interfaces xe-0/0/47 description codd-b01-em2
set interfaces xe-0/0/47 ether-options 802.3ad ae3
set interfaces ae0 description SERVER_web1
set interfaces ae0 aggregated-ether-options lacp active
set interfaces ae0 unit 0 family ethernet-switching interface-mode access
set interfaces ae0 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ae1 description SERVER2
set interfaces ae1 aggregated-ether-options lacp active
set interfaces ae1 unit 0 family ethernet-switching interface-mode access
set interfaces ae1 unit 0 family ethernet-switching vlan members FW-TRUST
set interfaces ae2 description codd-b01-internal-network
set interfaces ae2 mtu 9000
set interfaces ae2 aggregated-ether-options lacp active
set interfaces ae2 unit 0 family ethernet-switching interface-mode access
set interfaces ae2 unit 0 family ethernet-switching vlan members SILENT_WEB_INTERNAL
set interfaces ae3 description codd-a02-internal-network
set interfaces ae3 mtu 9000
set interfaces ae3 aggregated-ether-options lacp active
set interfaces ae3 unit 0 family ethernet-switching interface-mode access
set interfaces ae3 unit 0 family ethernet-switching vlan members SILENT_WEB_INTERNAL
set interfaces vlan unit 1 family inet address 144.10.10.11/27
set snmp description FW1
set snmp location PHL
set snmp view jweb-view-all oid .1 include
set snmp community T_CURVE view jweb-view-all
set snmp community T_CURVE authorization read-only
set snmp community T_CURVE clients 1.1.1.1/32
set forwarding-options storm-control-profiles default all
set routing-options static route 0.0.0.0/0 next-hop 144.10.10.10
set protocols dcbx interface all
set protocols lldp interface all
set protocols lldp-med interface all
set protocols igmp-snooping vlan all
set vlans FW-TRUST vlan-id 1
set vlans FW-TRUST l3-interface irb.1
set vlans FW-UNTRUST vlan-id 2
set vlans SILENT_WEB_INTERNAL vlan-id 80
set vlans default vlan-id 99
set vlans default l3-interface irb.99
set vlans devlan vlan-id 201
答案1
问题是交换机上的 MTU 与服务器上的 MTU 相同。交换机上的 MTU 需要稍微高一点。将 MTU 设置为 9214 即可解决问题。