MSR 36-40 老报如下错误

设备上配置了L2TP VPN和几条专线，老报如下内容错误，请问是什么原因？

%Dec 31 08:59:49:076 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access1 changed to up. %Dec 31 09:08:11:591 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access2 changed to up. %Dec 31 09:08:11:696 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access2 changed to up. %Dec 31 09:17:29:889 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access3 changed to up. %Dec 31 09:17:29:956 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access3 changed to up. %Dec 31 10:09:50:897 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access4 changed to up. %Dec 31 10:09:52:956 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access4 changed to up. %Dec 31 10:17:43:012 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access3 changed to down. %Dec 31 10:17:43:013 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access3 changed to down. %Dec 31 10:43:15:760 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access3 changed to up. %Dec 31 10:43:18:796 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access3 changed to up. %Dec 31 11:23:23:958 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access1 changed to down. %Dec 31 11:23:23:958 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access1 changed to down. %Dec 31 11:51:33:332 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access1 changed to up. %Dec 31 11:51:33:496 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access1 changed to up. %Dec 31 12:07:24:071 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access5 changed to up. %Dec 31 12:07:26:096 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access5 changed to up. %Dec 31 12:09:58:761 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access1 changed to down. %Dec 31 12:09:58:761 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access1 changed to down. %Dec 31 13:19:06:380 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access5 changed to down. %Dec 31 13:19:06:381 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access5 changed to down. %Dec 31 13:52:27:451 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access1 changed to up. %Dec 31 13:52:27:516 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access1 changed to up. %Dec 31 13:55:50:915 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access5 changed to up. %Dec 31 13:55:50:976 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access5 changed to up. %Dec 31 14:16:47:023 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access6 changed to up. %Dec 31 14:16:47:080 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access6 changed to up. %Dec 31 14:42:53:495 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access7 changed to up. %Dec 31 14:42:53:543 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access7 changed to up. %Dec 31 14:48:57:108 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access7 changed to down. %Dec 31 14:48:57:208 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access7 changed to down. %Dec 31 14:48:59:603 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access7 changed to up. %Dec 31 14:49:01:636 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access7 changed to up. %Dec 31 16:16:29:928 2021 MSR3640 IFNET/3/PHY_UPDOWN: Physical state on the interface Virtual-Access8 changed to up. %Dec 31 16:16:32:976 2021 MSR3640 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Virtual-Access8 changed to up.