Why is the error with seqno: -1 in grastate.dat

Products

• VMware Tanzu Application Service

Issue/Introduction

When executing the following command:

bosh -d <cf_guid> ssh mysql -c "sudo cat /var/vcap/store/pxc-mysql/grastate.dat | grep 'seqno:'"

 

We can see the output:

seqno: -1

Resolution

In the context of Galera (which PXC uses for replication), the grastate.dat file stores the last known state of the node.

The seqno (sequence number) indicates the last transaction this node had applied.

A value of -1 means: The node crashed or was killed abruptly, and no valid transaction state could be saved.