SELECT relname, reltuples, relpages * 8 / 1024 AS “MB” FROM pg_class ORDER BY relpages DESC;

original post

While working on ny NFS cluster project , I could not mount my nfs exports from clients ( FreBSD & Centos ).

on the FreeBSD client I got these responses :
[udp] server:/data/dir1: Permission denied
on the CentOS client I got these responses:
mount: server:/data/dir1 failed, reason given by server: Permission denied

On the Centos NFS server the logs showed :
mountd[12377]: authenticated mount request from client1:984 for /data/dir1 (/data/dir1)

Turns out there’s a bug in CentOS and modprobe does not mount the nfsd procs , you can fix the issue by adding :

none /proc/fs/nfsd nfsd auto 0 0

to /etc/fstab
or manually ( if you want to make sure that is the issue ) :

/bin/mount -t nfsd nfsd /proc/fs/nfsd

I am working on building a DRBD cluster and as with all cluster tools , you must have a synced time between nodes.

1. install ntp
yum -y install ntp
2. enable ntp on boot
chkconfig ntpd on
3.run a manual time sync before starting the service
ntpdate 0.pool.ntp.org
4. start the service
service ntpd start

follow this link : Dell OMSA 5.5 Linux repository

Install dependency :

sudo yum -y install perl-Net-SSLeay

Get the latest RPM from the Webmin website and install it

wget http://prdownloads.sourceforge.net/webadmin/webmin-1.441-1.noarch.rpm
rpm -ihv webmin-1.441-1.noarch.rpm

open port 10000 in your iptables :

sudo vi /etc/sysconfig/iptables

Add the following line :

-A RH-Firewall-1-INPUT -m state –state NEW -m tcp -p tcp –dport 10000 -j ACCEPT

Reload iptables :

sudo /sbin/service iptables restart

access your webmin install via browser :

https://your server name:10000/

Note: you should probably limit the ip’s that can access your webmin interface , cant be too careful now days…
this can be done by changing the above iptables line and add a “-s subnet or ip” , for example limit access to the 192.168.1.0 subnet only :

-A RH-Firewall-1-INPUT -m state –state NEW -m tcp -p tcp -s 192.168.1.0/24 –dport 10000 -j ACCEPT

and of course reload your iptables again.