Есть сервер FreeBSD 4.11-STABLE. Заметил что на нем все исходящие соединения идут с флагом DF. Никак не могу понять почему? Вот пример лога tcpdump:

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tcpdump -i ed0 -n host revolver.ru
tcpdump: listening on ed0
09:50:32.258644 x.x.x.x.4591 > 217.16.16.106.80: S 732277126:732277126(0) win 57344 <mss 1460,nop,wscale 0,nop,nop,timestamp 5248419 0> (DF) [tos 0x10]
09:50:32.361830 217.16.16.106.80 > x.x.x.x.4591: S 1113346761:1113346761(0) ack 732277127 win 57344 <mss 1460,nop,wscale 0,nop,nop,timestamp 135717580 5248419> (DF)
09:50:32.362225 x.x.x.x.4591 > 217.16.16.106.80: . ack 1 win 57920 <nop,nop,timestamp 5248429 135717580> (DF) [tos 0x10]
09:50:43.650812 x.x.x.x.4591 > 217.16.16.106.80: F 1:1(0) ack 1 win 57920 <nop,nop,timestamp 5249558 135717580> (DF) [tos 0x10]
09:50:43.751509 217.16.16.106.80 > x.x.x.x.4591: . ack 2 win 57920 <nop,nop,timestamp 135718719 5249558> (DF)
09:50:43.751909 217.16.16.106.80 > x.x.x.x.4591: F 1:1(0) ack 2 win 57920 <nop,nop,timestamp 135718719 5249558> (DF)
09:50:43.752023 x.x.x.x.4591 > 217.16.16.106.80: . ack 2 win 57919 <nop,nop,timestamp 5249568 135718719> (DF) [tos 0x10]
---8<--

Конфиг ядра:
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machine         i386
cpu             I686_CPU
ident           ARGO
maxusers        500

# COMPATIBILITY OPTIONS
options         COMPAT_43
options         COMPAT_LINUX

# FILESYSTEM OPTIONS
options         FFS                     #Berkeley Fast Filesystem
options         FFS_ROOT                #FFS usable as root device [keep this!]
options         MSDOSFS                 #MSDOS Filesystem
options         CD9660                  #ISO 9660 Filesystem
options         PROCFS                  #Process filesystem
options         QUOTA                   #enable disk quotas
options         SOFTUPDATES             #Enable FFS soft updates support
options         UFS_DIRHASH             #Improve performance on big directories
options         NFS                     #Network Filesystem

# NETWORKING OPTIONS
options         INET                    #InterNETworking
options         IPTUNNEL                #IP in IPX encapsulation (not available)

# Internet family options:
options         IPFIREWALL              #firewall
options         IPFIREWALL_VERBOSE      #print information about dropped packets
options         IPFIREWALL_FORWARD      #enable transparent proxy support
options         IPFIREWALL_VERBOSE_LIMIT=10    #limit verbosity
options         IPFIREWALL_DEFAULT_TO_ACCEPT    #allow everything by default
options         IPDIVERT                #divert sockets
options         TCP_DROP_SYNFIN         #drop TCP packets with SYN+FIN
options         ICMP_BANDLIM
options         DUMMYNET

# OTHER OPTIONS
options         CPU_ENABLE_SSE
options         UCONSOLE                #Allow users to grab the console
options         USERCONFIG              #boot -c editor
options         VISUAL_USERCONFIG       #visual boot -c editor
options         KTRACE                  #ktrace(1) support
options         SYSVSHM                 #SYSV-style shared memory
options         SYSVMSG                 #SYSV-style message queues
options         SYSVSEM                 #SYSV-style semaphores
options         P1003_1B                #Posix P1003_1B real-time extensions
options         _KPOSIX_PRIORITY_SCHEDULING
options         ICMP_BANDLIM            #Rate limit bad replies
options         KBD_INSTALL_CDEV        # install a CDEV entry in /dev
options         ENABLE_ALART
options         PANIC_REBOOT_WAIT_TIME=16
options         DEVICE_POLLING
options         SCSI_DELAY=15000        #Delay (in ms) before probing SCSI

device          isa
device          eisa
device          pci

# Floppy drives
device          fdc0    at isa? port IO_FD1 irq 6 drq 2
device          fd0     at fdc0 drive 0

# ATA and ATAPI devices
device          ata0    at isa? port IO_WD1 irq 14
device          ata1    at isa? port IO_WD2 irq 15
device          ata
device          atadisk                 # ATA disk drives
device          atapicd                 # ATAPI CDROM drives
device          atapifd                 # ATAPI floppy drives
device          atapist                 # ATAPI tape drives
options         ATA_STATIC_ID           #Static device numbering

# SCSI Controllers
device          ahc             # AHA2940 and onboard AIC7xxx devices

# SCSI peripherals
device          scbus           # SCSI bus (required)
device          da              # Direct Access (disks)
device          sa              # Sequential Access (tape etc)
device          pass            # Passthrough device (direct SCSI access)

# atkbdc0 controls both the keyboard and the PS/2 mouse
device          atkbdc0 at isa? port IO_KBD
device          atkbd0  at atkbdc? irq 1 flags 0x1
device          psm0    at atkbdc? irq 12

device          vga0    at isa?

# splash screen/screen saver
pseudo-device   splash

# syscons is the default console driver, resembling an SCO console
device          sc0     at isa? flags 0x100

device          agp             # support several AGP chipsets

# Floating point support - do not disable.
device          npx0    at nexus? port IO_NPX irq 13

# Serial (COM) ports
device          sio0    at isa? port IO_COM1 flags 0x10 irq 4
device          sio1    at isa? port IO_COM2 irq 3
device          sio2    at isa? disable port IO_COM3 irq 5
device          sio3    at isa? disable port IO_COM4 irq 9

# PCI Ethernet NICs that use the common MII bus controller code.
# NOTE: Be sure to keep the 'device miibus' line in order to use these NICs!
device          miibus          # MII bus support
device          fxp             # Intel EtherExpress PRO/100B (82557, 82558)
device          rl              # RealTek 8129/8139

# ISA Ethernet NICs.
# 'device ed' requires 'device miibus'
device          ed0     at isa? disable port 0x280 irq 10 iomem 0xd8000

# Pseudo devices - the number indicates how many units to allocated.
pseudo-device   loop            # Network loopback
pseudo-device   ether           # Ethernet support
pseudo-device   ppp     1       # Kernel PPP
pseudo-device   tun     4       # Packet tunnel.
pseudo-device   pty             # Pseudo-ttys (telnet etc)
pseudo-device   md              # Memory "disks"
pseudo-device   gif     4       # IPv6 and IPv4 tunneling
pseudo-device   faith   1       # IPv6-to-IPv4 relaying (translation)
pseudo-device   gzip            #Exec gzipped a.out's
pseudo-device   vn              #Vnode driver (turns a file into a device)

# The `bpf' pseudo-device enables the Berkeley Packet Filter.
# Be aware of the administrative consequences of enabling this!
pseudo-device   bpf             #Berkeley packet filter

options         PPP_BSDCOMP             #PPP BSD-compress support
options         PPP_DEFLATE             #PPP zlib/deflate/gzip support
options         PPP_FILTER              #enable bpf filtering (needs bpf)
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У кого есть идеи?