通过路由器桥(tftp-server)运行时PXE挂起

Question

我正在通过xinetd运行tftp服务器。当我直接或通过开关插入客户端设备时，它会正确启动。然而，我不能完全启动一个客户端设备通过路由器连接在桥接器模式。它获得DHCP租约确定，并开始下载文件，但随后超时。当它超时时，我不清楚该运行哪一步。实际上，在客户端完成下载start.elf的同一秒钟内，似乎出现了“超时”。

当我将我的笔记本电脑连接到桥接路由器并在tftp服务器地址上运行一个traceroute时，它可以访问：

Traceroute has started…

traceroute to 192.168.10.1 (192.168.10.1), 64 hops max, 72 byte packets
 1  192.168.10.1 (192.168.10.1)  10.906 ms  5.274 ms  4.500 ms

有什么方法可以更好地记录并知道哪个步骤是超时的，这样我就知道在哪里调试了吗？我已经在tftp可执行文件上运行-v -v，但是在那里找不到关于额外日志记录的更多信息。

这是/var/log/messages中的输出：

Apr  8 23:01:25 shepherd dnsmasq-dhcp[19671]: DHCPDISCOVER(eno1) da:0d:17:d4:30:3b
Apr  8 23:01:25 shepherd dnsmasq-dhcp[19671]: DHCPOFFER(eno1) 192.168.10.133 da:0d:17:d4:30:3b
Apr  8 23:01:25 shepherd in.tftpd[19022]: RRQ from 192.168.10.133 filename bootcode.bin
Apr  8 23:01:26 shepherd in.tftpd[19022]: Client 192.168.10.133 finished bootcode.bin
Apr  8 23:01:26 shepherd in.tftpd[19027]: RRQ from 192.168.10.133 filename bootsig.bin
Apr  8 23:01:26 shepherd in.tftpd[19027]: Client 192.168.10.133 File not found bootsig.bin
Apr  8 23:01:26 shepherd in.tftpd[19027]: sending NAK (1, File not found) to 192.168.10.133
Apr  8 23:01:26 shepherd dnsmasq-dhcp[19671]: DHCPDISCOVER(eno1) da:0d:17:d4:30:3b
Apr  8 23:01:26 shepherd dnsmasq-dhcp[19671]: DHCPOFFER(eno1) 192.168.10.133 da:0d:17:d4:30:3b
Apr  8 23:01:26 shepherd in.tftpd[19029]: RRQ from 192.168.10.133 filename 69d4303b/start.elf
Apr  8 23:01:26 shepherd in.tftpd[19029]: Client 192.168.10.133 File not found 69d4303b/start.elf
Apr  8 23:01:26 shepherd in.tftpd[19029]: sending NAK (1, File not found) to 192.168.10.133
Apr  8 23:01:26 shepherd in.tftpd[19030]: RRQ from 192.168.10.133 filename autoboot.txt
Apr  8 23:01:26 shepherd in.tftpd[19030]: Client 192.168.10.133 File not found autoboot.txt
Apr  8 23:01:26 shepherd in.tftpd[19030]: sending NAK (1, File not found) to 192.168.10.133
Apr  8 23:01:26 shepherd in.tftpd[19031]: RRQ from 192.168.10.133 filename config.txt
Apr  8 23:01:26 shepherd in.tftpd[19031]: Client 192.168.10.133 finished config.txt
Apr  8 23:01:26 shepherd in.tftpd[19032]: RRQ from 192.168.10.133 filename recovery.elf
Apr  8 23:01:26 shepherd in.tftpd[19032]: Client 192.168.10.133 File not found recovery.elf
Apr  8 23:01:26 shepherd in.tftpd[19032]: sending NAK (1, File not found) to 192.168.10.133
Apr  8 23:01:26 shepherd in.tftpd[19033]: RRQ from 192.168.10.133 filename start.elf
Apr  8 23:01:32 shepherd in.tftpd[19040]: RRQ from 192.168.10.133 filename fixup.dat
Apr  8 23:01:32 shepherd in.tftpd[19040]: Client 192.168.10.133 finished fixup.dat
Apr  8 23:01:37 shepherd in.tftpd[19033]: Client 192.168.10.133 finished start.elf
Apr  8 23:01:37 shepherd in.tftpd[19033]: Client 192.168.10.133 timed out

[adam@shepherd ~]$ cat /etc/xinetd.d/tftp
# default: off
# description: The tftp server serves files using the trivial file transfer \
#   protocol.  The tftp protocol is often used to boot diskless \
#   workstations, download configuration files to network-aware printers, \
#   and to start the installation process for some operating systems.
service tftp
{
    socket_type     = dgram
    protocol        = udp
    wait            = yes
    user            = root
    server          = /usr/sbin/in.tftpd
    server_args     = -v -v -s /tftpboot
    disable         = no
    per_source      = 11
    cps         = 100 2
    flags           = IPv4
}

Answer 1

要跟踪这个问题，您需要一个Wireshark流量捕获(即在TFTP服务器上)，以便真正了解数据包级别发生了什么。