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To allow user01 to copy any files as root from /from/directory/ to /to/directory/ add the following to /etc/sudors file:
user01 ALL = NOPASSWD: /bin/cp /from/directory/* /to/directory/
And this one is for the multi commands:
user01 ALL = NOPASSWD: /bin/cp /from/directory/* /to/directory/, /bin/rm -rv /to/directory/*, /bin/ls -la /to/direcotry/*
To enable the VNC session running on display :1 for an oracle user on the SUSE server, please create the file called after.local in /etc/init.d with 775 rights, the file should look like that:
slestest:~ # cat /etc/init.d/after.local
#!/bin/sh
/bin/su oracle -c "/usr/bin/vncserver :1 &"
Just check that you have tightvnc installed:
slestest:~ # rpm -qa|grep vnc
xorg-x11-Xvnc-7.4-27.81.7
tightvnc-1.3.9-81.13.1
slestest:~ #
root# cat /var/lib/nfs/rmtab
From the rpc.mountd(8) man page:
The rmtab File
The rpc.mountd daemon registers every successful MNT request by adding
an entry to the /var/lib/nfs/rmtab file. When receivng a UMNT request
from an NFS client, rpc.mountd simply removes the matching entry from
/var/lib/nfs/rmtab, as long as the access control list for that export
allows that sender to access the export.
Clients can discover the list of file systems an NFS server is cur-
rently exporting, or the list of other clients that have mounted its
exports, by using the showmount(8) command. showmount(8) uses other
procedures in the NFS MOUNT protocol to report information about the
server’s exported file systems.
Note, however, that there is little to guarantee that the contents of
/var/lib/nfs/rmtab are accurate. A client may continue accessing an
export even after invoking UMNT. If the client reboots without sending
a UMNT request, stale entries remain for that client in
/var/lib/nfs/rmtab.
Samba mangles a long filename into an 8.3 filename, for example:
-rw-r–r– 1 42781900 42781900 1432 Oct 16 21:00 2ZAOMT~P.XML
-rw-r–r– 1 42781900 42781900 1432 Sep 14 09:00 2ZCLAI~F.XML
-rw-r–r– 1 42781900 42781900 1432 Dec 3 21:00 2ZDTUD~9.XML
-rw-r–r– 1 42781900 42781900 66047 Sep 24 21:00 2ZG7PO~5.XML
Add “mangled names=no” to the [global] section in /etc/samba/smb.conf and then restart the smb service.
root# cat /etc/samba/smb.conf
–cut
[global]
unix charset = UTF-8
mangled names=no
–cut
root# systemctl restart smb
And now, everything is okay 😉
-rw-r–r– 1 42781900 42781900 1432 Oct 16 09:00 2016-10-16_09:00_Trading_Day_Exchange_Rate.xml
-rw-r–r– 1 42781900 42781900 1432 Oct 16 09:00 2016-10-16_09:00_Two_Day_Rolling_Wind_Forecast.xml
-rw-r–r– 1 42781900 42781900 1432 Oct 16 14:57 2016-10-16_14:57_Trading_Day_Exchange_Rate.xml
-rw-r–r– 1 42781900 42781900 1432 Oct 16 14:57 2016-10-16_14:57_Two_Day_Rolling_Wind_Forecast.xml
More information: http://www.oreilly.com/openbook/samba/book/ch05_04.html
Assuming, that a proxy server is on 172.16.12.1 IP address and listening on a port 3128.
root# export http_proxy=http://username:password@172.16.60.3:3128/
There are some messages that you do not want to see in the logs file. In this case I had the following:
Feb 3 11:41:05 bnmdns1 nrpe[19270]: Error: Could not complete SSL handshake. 1
Feb 3 11:41:05 bnmdns1 nrpe[19272]: Error: Could not complete SSL handshake. 1
Feb 3 11:41:13 bnmdns1 nrpe[19278]: Error: Could not complete SSL handshake. 1
Feb 3 11:41:13 bnmdns1 nrpe[19280]: Error: Could not complete SSL handshake. 1
Feb 3 11:41:15 bnmdns1 nrpe[19286]: Error: Could not complete SSL handshake. 1
To get rid of those unwanted messages add the following to /etc/syslog-ng/syslog-ng.conf file:
filter f_nrpe {match ("Error: Could not complete SSL handshake. 1");};
destination d_nrpe { file("/var/log/nrpe.log");};
log { source(src); filter (f_nrpe); destination(d_nrpe);};
In the above example the filter and destination have nrpe names, as they should. The match statement is not taking into account the facility or severity. Be sure the name chosen doesn’t exist as another filter or destination already specified in this file. If we were to test this, at this point we would have a /var/log/messages file with “Error: Could not complete SSL handshake. 1” line as well as a /var/log/nrpe.log with the same “Error: Could not complete SSL handshake. 1” messages. We now need to exclude these messages from being logged to /var/log/messages.
In the syslog-ng.conf file there is a line that starts with “filter f_message”. We need to exclude our filter from being logged here. If the default line looks like the following:
filter f_messages { not facility(news, mail) and not filter(f_iptables); };
Change it to the following:
filter f_messages { not facility(news, mail) and not filter(f_iptables) and not filter(f_nrpe); };
The modified “f_messages” filter will now exclude anything defined in the “f_nrpe” filter. Messages with “Error: Could not complete SSL handshake. 1” in them should only be found in the defined log file as specified under “d_nrpe”.
Now, restart syslog-ng and test this by using logger command:
logger "Error: Could not complete SSL handshake. 1"
The unwanted nrpe logs should be stored in /var/log/nrpe.log
Character Name Character
Accent `
Ampersand &
Angle Brackets < >
Apostrophe ’
Asterisk *
At Symbol @
Backslash
Braces [ ]
Brackets { }
Circumflex ^
Colon :
Comma ,
Dollar Sign $
Equal Sign =
Exclamation Point !
Hyphen –
Number Sign #
Parentheses ( )
Percent Symbol %
Period .
Pipe |
Plus Sign +
Question Mark ?
Quotation Mark “
Semicolon :
Forward Slash /
Tilde ~
Underscore _
Uppercase Letters A-Z
Lowercase Letters a-z
Numerals 0-9
To enable query logging use:
root# rndc querylog on
To disable query logging use:
root# rndc querylog off
Query logging can also be enabled by explicitly directing the queries category to a channel in the logging section of named.conf or by specifying “querylog yes;” in the options section of “named.conf”.
By default query logging will go to /var/log/messages to avoid this situation, create the logging channels:
logging {
channel default_file {
file "/var/log/named.log" size 100m;
severity dynamic;
print-time yes;
print-severity yes;
print-category yes;
};
channel queries_file {
file "/var/log/queries.log" size 100m;
severity dynamic;
print-time yes;
print-severity yes;
print-category yes;
};
category queries { queries_file; };
category default { default_file; };
};
Bind creates the “empty zones” by default. So, that is why the reverse DNS (the query type PTR) lookup does not work for a local addresses IP.
Define “empty-zones-enable no;” in named.conf this will work as you expect.
Also you can created reverse map zone for your local machines, for example:
zone "16.172.in-addr.arpa" IN {
type forward;
forwarders {172.16.53.50; 172.16.53.51; 172.16.53.52;};
forward only;
};
To limit the amount of memory a name server uses, use the max-cache-size options statement:
root# cat /etc/named.conf
options {
directory "/var/named";
max-cache-size 10m; // maximum cache size of 10MB
};
root#
This tells the name server to remove old, cached records early (i.e., before they’re stale) if the size of the cache reaches the limit.
Once this is set, you may also want to reduce the cleaning interval (the period at which the name server checks for stale records):
root# cat /etc/named.conf
options {
directory "/var/named";
max-cache-size 10m; // maximum cache size of 10MB
cleaning-interval 10; // clean cache every 10 minutes
};
root#
Also the following can be used the max-cache-ttl and max-ncache-ttl. These limit the time-to-live values of cached records and cached negative responses, respectively.
root# cat /etc/named.conf
options {
directory "/var/named";
max-cache-size 10m; // maximum cache size of 10MB
cleaning-interval 10; // clean cache every 10 minutes
max-cache-ttl 60; // limit cached record to a 60s TTL
max-ncache-ttl 60; // limit cache negative responses to a 60s TTL
};
root#
To disable caching, see this: Bind – disable caching