I have built an OpenWrt firmware for R7800, the source code is new from the github repo here:
https://github.com/coolsnowwolf/lede
The kernel version is 4.14.120.
I configure the WAN static IP, and configure a L2TP dialing through WAN(Campus network dialing needed). At first everything went OK, but Every time I turn it on for about four hours, it will crash itself.
Specifically, the first thing is that I can't connect to the Internet. At this time, I can still access other devices in the LAN, such as the remote desktop of my desktop PC. After a while, the LAN devices are also can't be accessed, including Luci's management interface 192.168.1.1. By saving the system's log file, I found that it seems that xl2tp crashes. The specific error location is as follows:
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.879803] Exception stack(0xdd4619d8 to 0xdd461a20)
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.887446] 19c0: 00000000 00000b01
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.892506] 19e0: 00000b00 dd460000 d8798240 da8b5120 d94aa9c0 00000000 00001400 000005ee
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.900669] 1a00: 00000000 00000014 dd76a380 dd461a28 c06d4ea8 c06d567c 00000113 ffffffff
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.908814] [<c030c08c>] (__irq_svc) from [<c06d567c>] (ip_do_fragment+0x5e4/0x66c)
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.916970] [<c06d567c>] (ip_do_fragment) from [<c06d6e7c>] (ip_output+0x50/0xb4)
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.924514] [<c06d6e7c>] (ip_output) from [<bf301a08>] (l2tp_xmit_skb+0x424/0x448 [l2tp_core])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.932149] [<bf301a08>] (l2tp_xmit_skb [l2tp_core]) from [<bf93c750>] (pppol2tp_xmit+0x168/0x2b4 [l2tp_ppp])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.940599] [<bf93c750>] (pppol2tp_xmit [l2tp_ppp]) from [<bf8a21f4>] (ppp_unregister_compressor+0x11c/0xd60 [ppp_generic])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.950583] [<bf8a21f4>] (ppp_unregister_compressor [ppp_generic]) from [<bf8a2c44>] (ppp_unregister_compressor+0xb6c/0xd60 [ppp_generic])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.961519] [<bf8a2c44>] (ppp_unregister_compressor [ppp_generic]) from [<bf8a468c>] (ppp_release+0x104/0x190 [ppp_generic])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.974017] [<bf8a468c>] (ppp_release [ppp_generic]) from [<bf8a4860>] (ppp_start_xmit+0x148/0x1a8 [ppp_generic])
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.985395] [<bf8a4860>] (ppp_start_xmit [ppp_generic]) from [<c0690914>] (dev_hard_start_xmit+0xc8/0x154)
Thu May 30 21:35:00 2019 kern.warn kernel: [13463.995543] [<c0690914>] (dev_hard_start_xmit) from [<c06b901c>] (sch_direct_xmit+0xbc/0x1cc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.005087] [<c06b901c>] (sch_direct_xmit) from [<c0690f38>] (__dev_queue_xmit+0x488/0x7b0)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.013685] [<c0690f38>] (__dev_queue_xmit) from [<c06a1830>] (neigh_xmit+0xe4/0x1bc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.021857] [<c06a1830>] (neigh_xmit) from [<bf59a414>] (nf_flow_offload_ip_hook+0x4f0/0x524 [nf_flow_table])
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.029857] [<bf59a414>] (nf_flow_offload_ip_hook [nf_flow_table]) from [<c06cabdc>] (nf_hook_slow+0x38/0xd4)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.039724] [<c06cabdc>] (nf_hook_slow) from [<c068be64>] (__netif_receive_skb_core+0x570/0xbdc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.049611] [<c068be64>] (__netif_receive_skb_core) from [<c0691aa4>] (netif_receive_skb_internal+0xc0/0xd4)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.058466] [<c0691aa4>] (netif_receive_skb_internal) from [<c0785d3c>] (br_handle_frame_finish+0x530/0x55c)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.068275] [<c0785d3c>] (br_handle_frame_finish) from [<c0785fe4>] (br_handle_frame+0x27c/0x2bc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.078084] [<c0785fe4>] (br_handle_frame) from [<c068c010>] (__netif_receive_skb_core+0x71c/0xbdc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.086853] [<c068c010>] (__netif_receive_skb_core) from [<c068e2cc>] (process_backlog+0xb0/0x164)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.095707] [<c068e2cc>] (process_backlog) from [<c0691ed4>] (net_rx_action+0x144/0x31c)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.104729] [<c0691ed4>] (net_rx_action) from [<c03015c8>] (__do_softirq+0xf0/0x264)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.112988] [<c03015c8>] (__do_softirq) from [<c031d008>] (irq_exit+0xdc/0x148)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.120706] [<c031d008>] (irq_exit) from [<c030e4c0>] (handle_IPI+0xb4/0x1ac)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.127730] [<c030e4c0>] (handle_IPI) from [<c03014b8>] (gic_handle_irq+0x9c/0xb8)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.135020] [<c03014b8>] (gic_handle_irq) from [<c030c08c>] (__irq_svc+0x6c/0x90)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.142477] Exception stack(0xdd461f80 to 0xdd461fc8)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.150056] 1f80: 00000001 00000000 00000000 c0315040 ffffe000 c0b03c74 c0b03c28 00000000
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.155094] 1fa0: 00000000 512f04d0 00000000 00000000 dd461fc8 dd461fd0 c030878c c0308790
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.163231] 1fc0: 60000013 ffffffff
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.171393] [<c030c08c>] (__irq_svc) from [<c0308790>] (arch_cpu_idle+0x38/0x44)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.174699] [<c0308790>] (arch_cpu_idle) from [<c034fc6c>] (do_idle+0xe8/0x1bc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.182336] [<c034fc6c>] (do_idle) from [<c034ffb4>] (cpu_startup_entry+0x1c/0x20)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.189363] [<c034ffb4>] (cpu_startup_entry) from [<423017cc>] (0x423017cc)
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.197172] ath10k_pci 0000:01:00.0: SWBA overrun on vdev 0, skipped old beacon
Thu May 30 21:35:00 2019 kern.warn kernel: [13464.204042] ath10k_pci 0001:01:00.0: SWBA overrun on vdev 0, skipped old beacon
Thu May 30 21:35:12 2019 daemon.notice xl2tpd[3002]: Maximum retries exceeded for tunnel 58306. Closing.
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: Terminating pppd: sending TERM signal to pid 3381
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Connection 25488 closed to 10.0.2.3, port 1701 (Timeout)
Thu May 30 21:35:12 2019 daemon.info pppd[3381]: Terminating on signal 15
Thu May 30 21:35:12 2019 daemon.info pppd[3381]: Connect time 223.7 minutes.
Thu May 30 21:35:12 2019 daemon.info pppd[3381]: Sent 952993484 bytes, received 1684379488 bytes.
Thu May 30 21:35:12 2019 daemon.notice netifd: Network device 'l2tp-VPN' link is down
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.warn pppd[3381]: Overriding mtu 1500 to 1428
Thu May 30 21:35:12 2019 daemon.warn pppd[3381]: Overriding mru 1500 to mtu value 1428
Thu May 30 21:35:12 2019 daemon.notice pppd[3381]: Connection terminated.
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info xl2tpd[3002]: Can not find tunnel 58306 (refhim=0)
Thu May 30 21:35:12 2019 daemon.debug xl2tpd[3002]: network_thread: unable to find call or tunnel to handle packet. call = 55818, tunnel = 58306 Dumping.
Thu May 30 21:35:12 2019 daemon.info pppd[3381]: Exit.
Thu May 30 21:35:13 2019 daemon.notice netifd: Interface 'VPN' is now down
Thu May 30 21:35:13 2019 daemon.notice netifd: Interface 'VPN' is setting up now
Thu May 30 21:35:18 2019 daemon.notice netifd: VPN (7553): Could not resolve server address
Thu May 30 21:35:23 2019 daemon.notice netifd: Interface 'VPN' is now down
Thu May 30 21:35:23 2019 daemon.notice netifd: Interface 'VPN' is setting up now
Thu May 30 21:35:28 2019 daemon.notice netifd: VPN (7645): Could not resolve server address
Thu May 30 21:35:33 2019 daemon.notice netifd: Interface 'VPN' is now down
Thu May 30 21:35:33 2019 daemon.notice netifd: Interface 'VPN' is setting up now
We can see the stack error was thrown from kernel, then xl2tp start to do strange things. Finally the system daemon start to up VPN link again and again, which causes the hole crash directly. I am nearly crazy for it.....
So to this problem, is there any solution?
And I also have a second problem. The device I tag to the LAN port often does not appear in the DHCP device overview. Why?