Vertica Blog

Vertica Blog

Checklists

Query Tuning with Vertica: Dos and Don’ts

Soniya Shah, Information Developer
June 18, 2018

This blog post was authored by Eugenia Moreno. Query tuning in Vertica is not an exact science. Recommendations differ based on your database. This document assumes that all nodes in the cluster are UP, your Vertica configuration is ok, and that v*perf tools have been executed. The following diagram shows the query flow in Vertica:...
Programmer

Saving an Apache Spark DataFrame to a Vertica Table

Soniya Shah, Information Developer
June 14, 2018

Before you save an Apache Spark DataFrame to a Vertica table, make sure that you have the following setup: • Vertica cluster • Spark cluster • HDFS cluster. The Vertica Spark connector uses HDFS as an intermediate storage before it writes the DataFrame to Vertica. This checklist identifies potential problems you might encounter when using...

Why is Vertica not Ingesting Data From Kafka?

Soniya Shah, Information Developer
June 14, 2018

Prerequisite: Verify that Vertica is up and running. If you want to troubleshoot why Vertica is not ingesting data from Kafka, follow this checklist. Step Task Results 1 Check whether Kafka is up and running. a. Examine the server log files for broker errors: If there are errors, consult the Kafka documentation. b. Examine the...

Rebalance Taking a Long Time

Soniya Shah, Information Developer
June 14, 2018

After you add a node to your Vertica cluster or remove a node from your cluster, Vertica rebalances the data across all the nodes. If rebalancing is taking a long time, review these steps to find out the probable cause. Pre-Requisites To ensure a successful rebalance of your cluster, before you start the rebalance, take...

Why is the Vertica Host Slow?

Soniya Shah, Information Developer
June 14, 2018

Symptoms: Sluggish response time Server is CPU-bound with a high load and too many processes. The host is possibly in a hung state, unable to make connections, or connections are hanging. Possible causes: Low available memory Too many concurrent active processes running Server actively using swap space To troubleshoot, follow this checklist: Step Task Results...

What Should I do When Vertica Host is Down?

Soniya Shah, Information Developer
June 14, 2018

Each member of a Vertica cluster is referred to as a host throughout this checklist. The Vertica process communicates to other Vertica nodes in a cluster. Node refers to the Vertica database software. If your host is down, follow this checklist: Step Task Results 1 The Vertica host is physically powered off. No status lights...

Debug Vertica Host Network Connectivity

Soniya Shah, Information Developer
June 14, 2018

If your host is physically available and the operating system is up and running, but you cannot access your network to the Vertica cluster, then external connections might not be possible. Client software connections are failing, and users are not able to ssh to the host. From observing a hardware console connection, it looks like...
Three 3D arrows, different colors pointing in different directions

Upgrading Vertica

Soniya Shah, Information Developer
June 14, 2018

Vertica adds new features and enhances existing features with every release. To access the new and improved features, upgrade to the latest release of Vertica. Prerequisites Before you upgrade, perform the following: Perform a full database backup. If upgrade is unsuccessful, a full back up allows you to roll back to your current version. You...

Expanding Your Cluster with New Nodes

Soniya Shah, Information Developer
June 14, 2018

Does your business need more storage? Consider adding nodes to your database if you need more storage. Vertica recommends that you add all new nodes at the same time. You can use this checklist to add nodes. These are basic steps. There are additional options discussed in the Vertica documentation. Step Task Results 1 Perform...

What Should I do if the Ancient History Mark is not Advancing?

Soniya Shah, Information Developer
June 14, 2018

If the AHM is not advancing, troubleshoot using this checklist: Step Task Results 1 Check whether the Last Good Epoch (LGE) is advancing. If the LGE is advancing, go to Step 2. If the LGE is not advancing, go to Step 5. 2 Check whether all nodes are UP. If all the nodes are UP,...
Programmer

What Should I do to Shut Down Vertica Node for Maintenance?

Soniya Shah, Information Developer
June 14, 2018

If you need to shut down a Vertica node for maintenance, follow this checklist. Step Task Results 1 Verify that all cluster nodes are UP. To avoid a long node recovery time after shutdown, if one or more nodes is DOWN, identify and restart them using the instructions in Restarting Vertica on a Host. 2...

What Should I do if my Node Recovery is Slow?

Soniya Shah, Information Developer
June 14, 2018

If you are running Vertica 7.2.x or later, perform recovery by table. For details, see Recovery By Table in the Vertica documentation. If you are running a Vertica version prior to 7.1.x, stop the ETL jobs and restart node recovery. Step Task Results 1 Monitor progress of recovery: If is_running = f, recovery completed. Repeat...