OGG-01194 – Oracle Golden Gate CHARSET mismatch

When entertaining the loathsome idea of shipping an established Oracle data set to MSSQL (SQL Server 2014, Oracle 12c, and OGG 12.3 in this case), you may run into an issue that presents itself in the following form in your EXTRACT report:

WARNING OGG-01194
EXTRACT task RINI9001 abended : Conversion from character set UTF-8 of source column <COLUMN_NAME> to character set windows-1252 of target column <COLUMN_NAME> failed because the source column contains a character 'ef 81 8a' at offset 123 that is not available in the target character set.

THE PROBLEM?:

Essentially, the issue is that you are trying to have your REPLICAT process convert Unicode data into a CHARSET where that Unicode character doesn’t exist. This is the default behaviour of REPLICAT, it will always try to convert source data charsets to the target machine native.

RESOLUTION:

This can be controlled with “SOURCECHARSET” parameter in your REPLICAT task param file. Specifically “SOURCECHARSET PASSTHRU”. Using this parameter will force REPLICAT to blindly import the source data and not try to convert it to the native charset of the target machine.

More information on SOURCECHARSET here

Monitor Pending Connections – Zen/Zevenet Load Balancers

In my working environment, we use (rather extensively) ZenLB (or as they are now know, Zevenet) Load Balancers. In production systems, sometimes the back-ends of an infrastructure, or the “real servers” behind the load balancers, can become unresponsive for whatever reason. A typical one that I see quite often is when using clustered MS Exchange Client Access servers behind a load balanced pool. IIS may lock up on one or multiple CAS’s causing the connections coming in from clients to be stored at LB level as “pending”.

This is fine, but in my experience, once the Zevenet LB racks up 1500+ pending connections on one of its farms, it quickly exhausts it’s available memory.

The following check is called by the Nagios NRPE agent installed locally on the LB (It’s just Debian 8 afterall)

#!/bin/bash
#
# ZenLB Pending/Established Connection Tracking v1.0 - Dave Byrne
#
hour=`date +%H`
pending=`cat /proc/net/nf_conntrack |grep SYN_SENT |grep dport='443|80' |wc -l`
established=`cat /proc/net/nf_conntrack |grep ESTABLISHED |grep dport='443|80' |wc -l`

if [ $pending -gt 5 ]
   then
      printf "CRITICAL - Pending connections above threshold! Pending: $pending -- Established: $establishedn"
   exit 2
elif [ $established -eq 0 ] && [ $hour -ge 8 ] && [ $hour -le 23 ];
   then
      printf "CRITICAL - No established connections! Pending: $pending -- Established: $establishedn"
   exit 2
else
      printf "OK - Pending connections at acceptable level. Pending: $pending -- Established: $establishedn"
   exit 0
fi

The check will go CRITICAL if pending connections across ANY of the farms goes above 5. It will also go CRITICAL is the established connections drops to 0 (probably bad). But I have limited this to a certain time frame, as I appreciate that there may well be 0 established connections at 4am!!

-Dave

Monitor MySQL Binary Replication Slave Status (Nagios NRPE)

If you have one or many MySQL Replication Slaves, you may need a handy way to monitor each slaves’ status within your existing Nagios Monitoring Platform. This handy NRPE based bash script will help you out…

Read On… ->

Monitor Daemonized FastNetMon Process in Debian (Nagios NRPE)

Running FastNetmon on a Debian system to monitor traffic flow on your network? Need a solution to monitor if the fastnetmon daemonized process ever crashes? Me neither until today… Here you go.

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Bash Application – Simpler Exim Queue Management

Ever get stuck trying to remember the exim/exiqgrep/xargs commands at that one critical moment when you need to stop 800,000 spam mail getting delivered to Hotmail accounts? Me too.. So I made this to help. My other monitoring & alert scripts should have told you by now that you have a spam outbreak, so you’ll know which sending host its coming from. Fire this application up on that host to quickly and effectively manage the items in the mail queue.

Read On… ->

Monitor PostFix Outbound Mail Queue + Email

Here we’ve got a very small, but effective script that alerts when a PostFix queue grows beyond a predefined limit. In my environment, PostFix is being used by an outbound relay. This script can work in tandem with my other mail queue monitoring script (Exim Mail Queue Monitor).

Read On… ->