очень уж ошибка какая-то нетипичная, а что пишет в система -> журнал событий ?
и почему-то тут
http://ftp.dlink.ru/pub/Router/DIR-620/Firmware/RevD/ нету прошивки 1.4.2, может какая-то от ростелекома.. хм
с такой прошивкой выдали
из журнала событий, в это время откл интернет:
Nov 11 21:42:49 udhcpc[968]: Entering renew state
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Sending renew...
Nov 11 21:42:49 udhcpc[968]: Entering rebinding state
Nov 11 21:42:49 udhcpc[968]: Lease of 10.51.224.231 obtained, lease time 43255
Nov 11 21:43:06 pppd[932]: System time change detected.
Nov 11 21:46:43 kernel: [ 481.140000] TX: allow IGMP
Nov 11 21:46:43 kernel: [ 481.160000] TX: allow IGMP
Nov 11 21:46:43 dnsmasq[969]: script process exited with status 1
Nov 11 21:53:18 kernel: [ 876.250000] TX: allow IGMP
Nov 11 21:53:18 kernel: [ 876.310000] TX: allow IGMP
Nov 11 21:59:54 kernel: [ 1272.560000] TX: allow IGMP
Nov 11 21:59:54 kernel: [ 1272.570000] TX: allow IGMP
Nov 11 22:06:49 kernel: [ 1687.930000] TX: allow IGMP
Nov 11 22:06:49 kernel: [ 1687.930000] TX: allow IGMP
Nov 11 22:13:25 kernel: [ 2083.080000] TX: allow IGMP
Nov 11 22:13:25 kernel: [ 2083.090000] TX: allow IGMP
Nov 11 22:15:25 dnsmasq[969]: script process exited with status 1
Nov 11 22:19:57 kernel: [ 2475.140000] TX: allow IGMP