IBD stalls if addnode peer is in IBD #34096

1. 
   davidgumberg commented at 3:59 am on December 18, 2025: contributor

   Starting with two fresh nodes A and B: If you start node A and (before node A completes IBD) start a second node B with -addnode={address of node A}, node B will stall and not proceed in IBD.

    0mkdir -p /tmp/nodea /tmp/nodeb
    1
    2cat > /tmp/nodea/bitcoin.conf << EOF
    3prune=1000
    4bind=127.0.0.1:8333
    5EOF
    6
    7cat > /tmp/nodeb/bitcoin.conf << EOF
    8prune=1000
    9rpcport=18331
   10bind=127.0.0.1:18335
   11addnode=127.0.0.1:8333
   12EOF
   

   and then start both nodes however you prefer, e.g.

   0bitcoind -datadir=/tmp/nodea --daemonwait
   1bitcoind -datadir=/tmp/nodeb --daemonwait
   

   And node B will not advance:

   0tail /tmp/nodeb/debug.log
   

   Shutdown node A and node B comes to life!:

   0bitcoin-cli -datadir=/tmp/nodea stop
   1tail /tmp/nodeb/debug.log
   

2. l0rinc referenced this in commit 1126d7ed43 on Dec 18, 2025
3. l0rinc referenced this in commit 549b08e4e8 on Dec 20, 2025
4. willcl-ark added the label P2P on Jan 14, 2026

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davidgumberg

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