Failed to write CA to ZIP file – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 7.6-8.9

Briefly, this error occurs when Elasticsearch is unable to write the Certificate Authority (CA) to a ZIP file. This could be due to insufficient permissions, lack of disk space, or a faulty file path. To resolve this issue, you can check and adjust the file permissions, ensure there is enough disk space, or verify the file path is correct. Additionally, check if the ZIP file is not corrupted or being used by another process.

This guide will help you check for common problems that cause the log ” Failed to write CA to ZIP file ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.

Log Context

Log “Failed to write CA to ZIP file” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 pkcs12.setKeyEntry("ca"; ca.certAndKey.key; ca.password; new Certificate[] { ca.certAndKey.cert });
 try (ZipEntryStream entry = new ZipEntryStream(zip; dirName + "/ca.p12")) {; ca.password);
 } catch (KeyStoreException | IOException | CertificateException | NoSuchAlgorithmException e) {
 throw new ElasticsearchException("Failed to write CA to ZIP file"; e);
 }  private void writeKibanaInfo(ZipOutputStream zip; String dirName; CertificateTool.CAInfo ca; Environment env) {
 final String caCertName = "elasticsearch-ca.pem";