Listen queue overflow



  • A few days ago my 2.2.6 pfSense router started getting really slow and periodically dropping traffic.

    Here's what i'm seeing in the system logs:

    Feb 4 09:13:50 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3316 occurrences)
    Feb 4 09:14:51 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3253 occurrences)
    Feb 4 09:15:51 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3782 occurrences)
    Feb 4 09:16:51 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3624 occurrences)
    Feb 4 09:17:53 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (4239 occurrences)
    Feb 4 09:18:54 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3796 occurrences)
    Feb 4 09:19:54 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3442 occurrences)
    Feb 4 09:20:56 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3387 occurrences)
    Feb 4 09:21:57 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3672 occurrences)
    Feb 4 09:22:57 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3696 occurrences)
    Feb 4 09:23:57 kernel: sonewconn: pcb 0xc99acdc8: Listen queue overflow: 8 already in queue awaiting acceptance (3291 occurrences)

    Here's a netstat:

    [2.2.6-RELEASE][admin@pfSense.localdomain]/var/log: netstat -LaAn
    Current listen queue sizes (qlen/incqlen/maxqlen)
    Tcpcb    Proto Listen        Local Address   
    c862e2f0 tcp6  0/0/5          *.53             
    c85c2000 tcp4  8/0/5          *.53             
    c85c2bc0 tcp6  0/0/128        *.80             
    c85c3000 tcp4  0/0/128        *.80             
    c85c32f0 tcp6  0/0/128        *.4333           
    c85c35e0 tcp4  0/0/128        *.4333           
    c85c9bc0 tcp4  0/0/128        *.22             
    c85ca000 tcp6  0/0/128        *.22             
    Netgraph sockets
    PCB      Type  Recv-Q Send-Q Node Address  #Hooks
    c8f85900 ctrl      0      0 [6]:              0
    c795c400 ctrl      0      0 [4]:              0
    unix  0/0/3          /var/run/charon.vici
    unix  0/0/10        /var/run/charon.ctl
    unix  0/0/10        /var/run/charon.wlst
    unix  0/0/1          /var/etc/openvpn/client3.sock
    unix  0/0/1          /var/etc/openvpn/server2.sock
    unix  0/0/1          /var/etc/openvpn/server1.sock
    unix  0/0/4          /var/run/devd.pipe
    unix  0/0/30        /var/run/check_reload_status
    unix  0/0/128        /var/run/php-fpm.socket
    unix  0/0/4          /var/run/devd.seqpacket.pipe

    Appears this may be related to DNS? I can't figure out how to isolate the issue.

    Any assistance would be much appreciated - I can provide any details needed.