em(4) VLAN + PROMISC followup question

From: Jon Simola (jsimola_at_gmail.com)
Date: 01/26/05

  • Next message: Jeremie Le Hen: "Re: em(4) VLAN + PROMISC followup question" 
    Date: Wed, 26 Jan 2005 12:57:41 -0800
To: "freebsd-net@freebsd.org" <freebsd-net@freebsd.org>

    Referencing:
    http://lists.freebsd.org/pipermail/freebsd-net/2004-November/005738.html

    I appear to have hit a similar or the same problem (with the exception
    that I'm not bridging with the vlan), has anyone (Robert Watson
    appears to be the lead) come up with anything?

    My config is 5.3-STABLE with em1 the parent for a handful of vlans.
    em1: flags=18843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,POLLING> mtu 1500
            options=5b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,POLLING>
            inet6 fe80::230:48ff:fe72:f30b%em1 prefixlen 64 scopeid 0x6
            ether 00:30:48:72:f3:0b
            media: Ethernet autoselect (1000baseTX <full-duplex>)
            status: active
    vlan120: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
            inet xxx.xx.177.254 netmask 0xffffff00 broadcast 209.53.177.255
            inet6 fe80::205:5dff:fe71:8d20%vlan120 prefixlen 64 scopeid 0xd
            ether 00:30:48:72:f3:0b
            media: Ethernet autoselect (1000baseTX <full-duplex>)
            status: active
            vlan: 120 parent interface: em1

    Running a tcpdump on either em1 or one of the vlan interfaces reduces
    throughput by a factor of 10 or so. Running tcpdump with the -p option
    does not.

    This is a steady stream of 10 to 20 Mbps of traffic, routing 11 /24s
    over 4 vlans, kernel polling is enabled for the em devices.

    Thank you,
    Jon Simola
    Systems Administrator
    ABC Communications
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  • Next message: Jeremie Le Hen: "Re: em(4) VLAN + PROMISC followup question"

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