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Cisco Bug: CSCtd74470 - E1 R2 configured voice port, intermittently stuck in clearfwd state

Last Modified

Mar 08, 2018

Products (1)

  • Cisco 2800 Series Integrated Services Routers

Known Affected Releases


Description (partial)

Symptoms: Voice ports on gateways configured for E1 R2 intermittently get 
 stuck in the "clearfwd" state and can only be returned to normal operation 
 mode by manual intervention.
 Conditions: When the issue occurs, the following states are observed by 
examining the stuck port with <CmdBold>show<noCmdBold> commands:
 Router#sh vo po su | include clearfwd 0/3/0:1 24 r2-digital up up clearfwd 
 idle y
 Show voice trace 0/3/0.1.24
 0/3/0:1 24 State Transitions: timestamp (state, event) -> (state, event) ... 
 3440023.272 (R2_Q421_IDLE, E_HTSP_SETUP_REQ) -> 3440023.380 
 (R2_Q421_OG_SEIZE, E_DSP_SIG_1100) -> 3440047.816 (R2_Q421_OG_SEIZE_ACK, 
 E_R2_REG_ABORT_DIGIT_COLLECT) -> 3440047.816 (R2_Q421_OG_CLR_FWD, 
 > 3440050.816 (R2_Q421_WAIT_IDLE, E_HTSP_EVENT_TIMER) -> 3440050.816 
 (R2_Q421_WAIT_IDLE, E_DSP_SIG_1100) -> 3440050.820 (R2_Q421_BLOCKED, 
 E_DSP_SIG_1100) -> 3440069.960 (R2_Q421_BLOCKED, E_HTSP_RELEASE_REQ) -> 
 3440113.512 (R2_Q421_BLOCKED, E_DSP_SIG_1000) ->) ->

Related Community Discussions

E1 R2 : R2_Q421_BLOCKED
Dear   I have a probleme about R2 channels Block (r2_q421_blocked), when channels are blocked, i shut/no shut under controller E1, the channels unblock and after a while they become block.   We use a 2800 (IOS 12.4) as a voice-gateway, connected to Huawei MA5600.   This is the conf of the E1 ports : ---------------------------- controller E1 0/0/0  framing NO-CRC4  ds0-group 0 timeslots 1-15,17-31 type r2-digital r2-compelled ani  cas-custom 0  debounce-time 10  release-guard-time 10  seizure-ack-time ...
Latest activity: Jun 12, 2018
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Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
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  • Related Community Discussions
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