networking protocol_error ai_generated partial

PPPoE: LCP echo timeout, no response from peer 192.168.100.1

ID: networking/pppoe-lcp-echo-timeout

Also available as: JSON · Markdown · 中文
72%Fix Rate
82%Confidence
1Evidence
2023-11-08First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
pppd 2.4.9 active
pppd 2.5.1 active
Linux kernel 5.10 active

Root Cause

The PPPoE session's Link Control Protocol (LCP) echo requests are not being acknowledged by the remote peer, typically due to a dead access concentrator, a faulty DSL modem, or a misconfigured PPPoE server that has dropped the session silently.

generic

中文

PPPoE会话的链路控制协议(LCP)回显请求未得到远程对端的确认,通常是由于接入集中器失效、DSL调制解调器故障或PPPoE服务器静默断开会话。

Official Documentation

https://ppp.samba.org/pppd.html

Workarounds

  1. 80% success killall pppd && pon dsl-provider
    killall pppd && pon dsl-provider
  2. 85% success reboot modem via web interface or power cycle; then restart pppd: ifdown ppp0 && ifup ppp0
    reboot modem via web interface or power cycle; then restart pppd: ifdown ppp0 && ifup ppp0

中文步骤

  1. killall pppd && pon dsl-provider
  2. reboot modem via web interface or power cycle; then restart pppd: ifdown ppp0 && ifup ppp0

Dead Ends

Common approaches that don't work:

  1. Setting lcp-echo-interval to a larger value (e.g., 60 seconds) to reduce timeout frequency. 80% fail

    This only delays the inevitable disconnection; the underlying peer unresponsiveness remains, and sessions still drop after the longer timeout.

  2. Adding 'noecho' option to pppd to stop sending LCP echo requests. 95% fail

    Hides the failure but leaves the session in a broken state; the PPPoE connection may appear up but cannot pass traffic.