Percona Mysql Xtra DB Cluster 8.4.5

Trouble Connecting 2nd Node in Percona XtraDB Cluster – “certificate signature failure” (SSL)

Hi community,I’m setting up a 2-node Percona XtraDB Cluster (PXC 8.0.34) with SSL-based Galera cluster encryption.

Node 1:

Running fine with:

/etc/mysql/ssl/server-key.pem and server-cert.pem

CA signed with ca.pem, ca-key.pem

Cluster size shows as 1

SSL key and cert verified via:

openssl rsa -noout -modulus -in server-key.pem | openssl md5

openssl x509 -noout -modulus -in server-cert.pem | openssl md5

openssl verify -CAfile ca.pem server-cert.pem

Node 2:

Certificates created using:

openssl req -newkey rsa:4096 …

openssl x509 -req -CA ca.pem -CAkey ca-key.pem …

Correctly placed in /etc/mysql/ssl/, ownership and permissions set.

But MySQL fails to start on Node 2 with:

Galera: Failed to establish connection: data too large for modulus: certificate signature failure

wsrep.cnf (common for both nodes):

[mysqld]

wsrep_provider = /usr/lib/galera4/libgalera_smm.so

wsrep_cluster_name = mycluster

wsrep_cluster_address = gcomm://<node1_ip>

wsrep_node_address = <respective_ip>

wsrep_node_name = <node_name>

pxc-encrypt-cluster-traffic=ON

[sst]

ssl-ca = /etc/mysql/ssl/ca.pem

ssl-cert = /etc/mysql/ssl/server-cert.pem

ssl-key = /etc/mysql/ssl/server-key.pem

[xtrabackup]

ssl-ca = /etc/mysql/ssl/ca.pem

ssl-cert = /etc/mysql/ssl/server-cert.pem

ssl-key = /etc/mysql/ssl/server-key.pem

What I’ve Tried:

Regenerated certs with 2048-bit keys on Node 2 (same CA).

Verified cert/key pair on both nodes.

Ensured same CA files are in use.

Restarted MySQL after full cleanup.

Still getting:

certificate signature failure / data too large for modulus

You don’t need to generate certificate on Node2. Here you need to copy the certificate from Node1 to Node2 and keep using the same certificates across the cluster nodes.

you should use the same key and certificate files on all nodes

I am very thankful to you sir,resolved!

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