OS, Linux, Oracle Engineered Systems, Cloud Services.
Quick one!
# Warnings
cat /var/log/mysqld.log |grep `date +%y%m%d` | grep "\[Warning\]"
# Errors
cat /var/log/mysqld.log |grep `date +%y%m%d` | grep "\[ERROR\]"
And a Bonus!
To get entries from X days ago:
cat /var/log/mysqld.log |grep `date --date="46 days ago" +%y%m%d`
Matheus.
Hi all,
I always forget the command and have to search it again. For further searches, I expect to found in my own posts… 🙂
> To start Service
startsrc -s xntpd
> To stop Service
stopsrc -s xntpd
> Configuration File
/etc/ntpd.conf
Expect it be useful to you too.
See ya!
Matheus.
Hi folks!
Today a friend asked about how to configure disks on VMWare to create a virtualized cluster database. I revisited my old notes and decided to share. Here it goes…
First, I really have some constraints about it:
– Fake “high availability”: To have HA with VM it’s not needed 2 vms, if a host fail VMWare should make a VMotion (if well configured), and no services will be affected. So, one VM is ok.
– Not real “horizontally scallated”: It probably would be better to use one server as physical than have two vms on it. Not make sense to do it…
So, why?
To prove concept, evaluate RAC configuration (caches on sequences, etc) and labs, to learn and practice RAC stuffs…
Ok, now how to make it happen?
1. Add new disk to one of the machines. Some way, one will be the “primary” and share disks with another.
2. Set Mode Thick Eager Zeroed
3. Create a specific controller to this “shared disks”
4. Set controller to virtual sharing
# Other Machine
5. Adding the existent disk to other VM (not primary, but from primary)
6. Select disk from primary
7. Create a new controller, as you made on primary and select it:
8. Set controller to virtual sharing
OBS:
If this error happen, one of your controller is not in sharing mode. Please check it.
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And here we are! 🙂
Good lab!
Matheus.
Hi all!
Quick one to resize swap online:
[root@server-db ~]# swapon -s Filename                               Type           Size   Used   Priority /dev/mapper/rootvg-lvswap             partition      5242872 373624 -1 [root@server-db ~]# vgs VG               #PV #LV #SN Attr  VSize  VFree [...] rootvg             1  6  0 wz--n- 135.69G 5.69G [...] [root@server-db ~]# lvextend -L +2048M /dev/mapper/rootvg-lvswap Extending logical volume lvswap to 7.00 GB Logical volume lvswap successfully resized [root@server-db ~]# vgs VG               #PV #LV #SN Attr  VSize  VFree [...] rootvg             1  6  0 wz--n- 135.69G 3.69G [...] [root@server-db ~]# mkswap /dev/mapper/rootvg-lvswap Setting up swapspace version 1, size = 7516188 kB [root@server-db ~]# swapoff /dev/mapper/rootvg-lvswap [root@server-db ~]# swapon /dev/mapper/rootvg-lvswap [root@server-db ~]# swapon -s Filename                               Type           Size   Used   Priority /dev/mapper/rootvg-lvswap             partition      7516188 373624 -1
See ya!
Matheus.
Hi all!
As you know, we have some commercial solutions to monitoring/alerting MySQL, like MySQL Enterprise Monitor or Oracle Grid/Cloud Control.
But, regarding we are using MySQL instead of Oracle Database, we can assume it’s probably a decision taken based on cost. So, considering Open Source solutions, we basically have Nagios, Zabbix, OpenNMS…
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Thinking on Nagios, in my opinion the “supra sumo” is mysql_health_check.pl.
Below whitepaper and presentation:
White Paper
Presentation
Code
Good one by Sheeri Cabral and posted here!
Any way, with theese two we can make lots of magic:
1. check_mysql.pl
– Check status of MySql server (slow queries, etc)
– Queries per second graph
2. check_db_query.pl
– Allowes to run SQL Queries and setting thresholds for warning e critical. Ex:
check_db_query.pl -d database -q query [-w warn] [-c crit] [-C conn_file] [-p placeholder]
Ex for Nagios call:
define command{
command_name   check_db_entries
command_line   /usr/local/bin/perl $USER1$/check_db_query.pl -d "$ARG1$" -q "$ARG2$" $ARG3$
}
So, now it’s just make your queries and implement your free monitoring on MySQL! 🙂
Matheus.
A quick script to do that:
grep line /sys/devices/system/memory/*/state | while read bla;
do echo online /sys/devices/system/memory/memory${bla}/state; done
Have a nice day!
Matheus.
From disk to filesystem:
> Rescan on scisi controller to detect the disk (controller id 0, in this example)
echo "- - -" > /sys/class/scsi_host/host0/scan
– List disks
fdisk -l
> Fdisk choosing options n -> new p->partition 1-> partition number
fdisk /dev/sdm
> Create physcal volume
pvcreate /dev/sdm1
> Create Volume Group
vgcreate oracle /dev/sdb1
> Rename Volume Group
vgrename oracle vgoracle
> Create LV
lvcreate -L 19G -n lvoracle vgoracle
> Extend LV
lvextend -L +990M /dev/vgoracle/lvoracle
> Make FileSystem
mkfs.ext3 -m 0 -v /dev/vgoracle/lvoracle
OBS: m 0 is the journal (for recovery in case of crash). “0” because I don’t want it now. So, 100% of disco will be available for using on fs.
> Mount filesystem on Directory
mount -t ext3 /dev/vgoracle/lvoracle /oracle/
> Just to check:
$ df -h /dev/mapper/vgoracle-lvoracle 20GÂ 173MÂ Â 20GÂ Â 1% /oracle
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Have a nice day!
Matheus.
# Problem
myserver:/home/oracle>srvctl start database -d mydb PRCR-1079 : Failed to start resource ora.mydb.db CRS-5017: The resource action "ora.mydb.db start" encountered the following error: ORA-27102: out of memory Linux-x86_64 Error: 28: No space left on device . For details refer to "(:CLSN00107:)" in "/grid/product/11.2.0/log/myserver/agent/crsd/oraagent_oracle/oraagent_oracle.log". CRS-2674: Start of 'ora.mydb.db' on 'myserver' failed CRS-5017: The resource action "ora.mydb.db start" encountered the following error: ORA-27102: out of memory Linux-x86_64 Error: 28: No space left on device . For details refer to "(:CLSN00107:)" in "/grid/product/11.2.0/log/myserver2/agent/crsd/oraagent_oracle/oraagent_oracle.log". CRS-2674: Start of 'ora.mydb.db' on 'myserver2' failed CRS-2632: There are no more servers to try to place resource 'ora.mydb.db' on that would satisfy its placement policy myserver:/home/oracle>
# Solution
On /etc/sysctl.conf ajust as below and then reload sysctl (“sysctl -p” as root):
#Old #kernel.shmall = 24641536 #New kernel.shmall = 4294967296
Matheus.
Supposing you are in a server shell and don’t know if you machine is virtualized (a VM)?
One way to check that (supposing VMWare as hypervisioning solution) is:
[root@mydbsrvr ~]# dmidecode | grep -i vmware Manufacturer: VMware, Inc. Product Name: VMware Virtual Platform Serial Number: VMware-xx xx xx xx xx xx xx xx-xx xx xx xx xx xx xx xx Description: VMware SVGA II
If you had an answer like this, yes, it’s a VM. 🙂
Matheus.