PPPキープアライブ
珍しい、LCPエコーリクエスト ３回リトライエラーでルーターが
PPPoEを再接続した。
今更だが、ラズパイルーターのPPPキープアライブも正常動作を確認（笑）
ラズパイルーターだからリンクダウンの原因も判りストレスが少ない。
以下、syslogの関連箇所抜粋
Jun 1 09:27:34 gw pppd[416]: No response to 3 echo-requests
Jun 1 09:27:34 gw pppd[416]: Serial link appears to be disconnected.
Jun 1 09:27:34 gw pppd[416]: Connect time 8215.7 minutes.
Jun 1 09:27:34 gw pppd[416]: Sent 2088129687 bytes, received 9618988 bytes.
Jun 1 09:27:35 gw ntpd[489]: Deleting interface #6 ppp0, 59.146.14.24#123, interface stats: received=0, sent=0, dropped=0, active_time=342372 secs
Jun 1 09:27:35 gw ntpd[489]: 133.243.238.163 interface 192.168.1.254 -> (none)
Jun 1 09:27:35 gw ntpd[489]: peers refreshed
Jun 1 09:27:40 gw pppd[416]: Connection terminated.
Jun 1 09:27:40 gw pppd[416]: Modem hangup
Jun 1 09:27:43 gw dnsmasq[509]: reading /etc/resolv.conf
Jun 1 09:27:43 gw dnsmasq[509]: using nameserver 202.238.95.9#53
Jun 1 09:27:43 gw dnsmasq[509]: using nameserver 202.238.95.22#53
Jun 1 09:28:45 gw pppd[416]: Timeout waiting for PADO packets
Jun 1 09:28:45 gw pppd[416]: Unable to complete PPPoE Discovery
Jun 1 09:29:50 gw pppd[416]: Timeout waiting for PADO packets
Jun 1 09:29:50 gw pppd[416]: Unable to complete PPPoE Discovery
Jun 1 09:30:26 gw pppd[416]: PPP session is 20582
Jun 1 09:30:26 gw pppd[416]: Connected to 0e:ba:01:02:00:63 via interface eth1
Jun 1 09:30:26 gw pppd[416]: Using interface ppp0
Jun 1 09:30:26 gw pppd[416]: Connect: ppp0 <--> eth1
Jun 1 09:30:26 gw pppd[416]: CHAP authentication succeeded
Jun 1 09:30:26 gw pppd[416]: CHAP authentication succeeded
Jun 1 09:30:26 gw pppd[416]: peer from calling number 0E:BA:01:02:00:63 authorized
Jun 1 09:30:26 gw pppd[416]: local IP address 220.211.168.235
Jun 1 09:30:26 gw pppd[416]: remote IP address 61.211.9.29
Jun 1 09:30:26 gw pppd[416]: primary DNS address 202.238.95.9
Jun 1 09:30:26 gw pppd[416]: secondary DNS address 202.238.95.22
Jun 1 09:30:27 gw ntpd[489]: Listen normally on 8 ppp0 220.211.168.235 UDP 123
Jun 1 09:30:27 gw ntpd[489]: peers refreshed
Jun 1 09:30:30 gw dnsmasq[509]: reading /etc/resolv.conf
Jun 1 09:30:30 gw dnsmasq[509]: using nameserver 202.238.95.9#53
Jun 1 09:30:30 gw dnsmasq[509]: using nameserver 202.238.95.22#53