Can’t edit /etc/resolv.conf with root account problem.

  • A file is set with ‘i‘ attribute, cannot be modified (immutable). Means no renaming, no symbolic link creation, no execution, no writable, only superuser can unset the attribute.
  •  we use the + sign and to unset use the – sign with the chattr command.
    + : Adds the attribute to the existing attribute of the files.
    – : Removes the attribute to the existing attribute of the files.
    = : Keep the existing attributes that the files have.
vi /etc/resolv.conf 
/etc/resolv.conf" [readonly] 12L, 301C 
[root@rhel6 ~]# lsattr /etc/resolv.conf
----i--------e- /etc/resolv.conf
[root@rhel6 ~]# chattr -i /etc/resolv.conf
[root@rhel6 ~]# lsattr /etc/resolv.conf
-------------e- /etc/resolv.conf
[root@rhel6 ~]# vi /etc/resolv.conf
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-bash: /bin/rm: Argument list too long wile removing files

Problem:

I have a directoy in linux that has several hundred thousand files, and is about 8.2 Gb. I attempted to clear out the directory using ‘rm -rf *aud’, and got the following error:

Oracle audit files:

[oracle@drexa01dbadm01 rdbms]$ du -sh audit
8.2G audit
[oracle@drexa01dbadm01 rdbms]$ cd audit/
[oracle@drexa01dbadm01 audit]$pwd
/u01/app/oracle/product/12.1.0.2/dbhome_1/rdbms/audit
[oracle@drexa01dbadm01 audit]$ rm -rf *aud
-bash: /bin/rm: Argument list too long
[oracle@drexa01dbadm01 audit]$

Solution:

[root@drexa01dbadm01 audit]# find . -name '*aud' | xargs rm -v
removed `./opum_ora_5570_20170419113001272611143795.aud'
removed `./opum_ora_19087_20170825213720316402143795.aud'
removed `./opum_ora_24477_20170215033002283227143795.aud'
removed `./opum_ora_7691_20160815080001986930143795.aud'
removed `./opum_ora_16653_20160907043002231684143795.aud'
removed `./opum_ora_13406_20170127234157760483143795.aud'
removed `./opum_ora_20966_20160830140953226189143795.aud'
removed `./opum_ora_32328_20160302052636008652143795.aud'
removed `./opum_ora_8918_20170924193849158242143795.aud'
removed `./opum_ora_3496_20160915031853572953143795.aud'
removed `./opum_ora_6372_20161020181850094006143795.aud'
removed `./opum_ora_14855_20161014233431338219143795.aud'
removed `./opum_ora_3543_20160320162656730084143795.aud'
removed `./opum_ora_507_20171004204104885761143795.aud'
removed `./opum_ora_28535_20160510060437060235143795.aud'
removed `./opum_ora_12919_20170501052812370394143795.aud'
removed `./opum_ora_19556_20161209185701631815143795.aud'
removed `./opum_ora_4558_20170821004123546569143795.aud'
removed `./opum_ora_12780_20170113235941423540143795.aud'
removed `./opum_ora_7448_20160602072824080487143795.aud'
removed `./opum_ora_25740_20160704060001516869143795.aud'
removed `./opum_ora_18222_20170211181055180098143795.aud'
removed `./opum_ora_14988_20160619075753542821143795.aud'
removed `./opum_ora_18060_20170510231755910407143795.aud'
removed `./opum_ora_4974_20160904032946872225143795.aud'
removed `./opum_ora_22492_20160810164246080476143795.aud'
removed `./opum_ora_30220_20160730184335973711143795.aud'
removed `./opum_ora_9281_20160601050646550905143795.aud'
removed `./opum_ora_23802_20161007002846100802143795.aud'
removed `./opum_ora_31124_20170722151749240758143795.aud'
removed `./opum_ora_19994_20160603044311483365143795.aud'
removed `./opum_ora_12052_20160228214028001728143795.aud'
removed `./opum_ora_15291_20170914184724665451143795.aud'
removed `./opum_ora_22103_20160603225229269785143795.aud'
removed `./opum_ora_16853_20170731031019341399143795.aud'
removed `./opum_ora_17237_20170418113002372693143795.aud'
removed `./opum_ora_6563_20161224000002747653143795.aud'
removed `./opum_ora_25523_20170623172237509923143795.aud'
removed `./opum_ora_31895_20160806180001664608143795.aud'

 

 

 

Permissions on the password database may be too restrictive. su: incorrect password Problem

Environment

  • SLES for SAP Applications 11.4 (x86_64)
  • SUSE Linux Enterprise Server 11 (x86_64)

Issue

  • Permissions on the password database may be too restrictive.
    su: incorrect password

Resolution

  • Re-create the oragrid user.

agrcpgd1:oraegp 54> su – oragrid
Password:
Permissions on the password database may be too restrictive.
su: incorrect password

  • check user id and group id 

agrcpgd1:~ # cat /etc/passwd| grep oragrid
oragrid:x:507:503:Grid Admin:/home/oragrid:/bin/bash
agrcpgd1:~ # id oragrid
uid=507(oragrid) gid=503(dba) groups=503(dba)

  • Remove oragrid user without -r option.(-r option:To remove the user’s home directory and mail spool )

agrcpgd1:~ # userdel oragrid
no crontab for oragrid

  • Add user with userid and groupid.

agrcpgd1:~ # useradd -u 507 -g 503 -c “Grid Admin” -d /home/oragrid oragrid
agrcpgd1:~ # passwd oragrid
Changing password for oragrid.
New Password:
Reenter New Password:
Password changed.

agrcpgd1:oraegp 51> su – oragrid
Password:
oragrid@agrcpgd1:~>

ORA-15032, ORA-15040, ORA-15042 Error on Oracle ASM

ERROR:Try to mount the disk group on ASM

SQL> alter diskgroup RECOc1 mount;

alter diskgroup RECOc1 mount

*

ERROR at line 1:

ORA-15032: not all alterations performed

ORA-15040: diskgroup is incomplete

ORA-15042: ASM disk “2” is missing from group number “2”

Check  Alert Log:

Wed Feb 15 15:32:15 2017
NOTE: Disk RECOC1_0000 in mode 0x7f marked for de-assignment
NOTE: Disk RECOC1_0001 in mode 0x7f marked for de-assignment
ERROR: diskgroup RECOC1 was not mounted
ORA-15032: not all alterations performed
ORA-15040: diskgroup is incomplete
ORA-15042: ASM disk “2” is missing from group number “2”

 

SOLUTION:

All transactions must be done by root user.

1-Scan and find RECOC1 disks with scripts;

/etc/init.d/oracleasm querydisk -d `/etc/init.d/oracleasm listdisks -d` | \

cut -f2,10,11 -d” ” | \

perl -pe ‘s/”(.*)”.*\[(.*), *(.*)\]/$1 $2 $3/g;’ | \

while read v_asmdisk v_minor v_major

do

v_device=`ls -la /dev | grep ” $v_minor, *$v_major ” | awk ‘{print $10}’`

echo “ASM disk $v_asmdisk based on /dev/$v_device [$v_minor, $v_major]”

done

2-Remove RECOC* found disks

/etc/init.d/oracleasm deletedisk RECOC1

/etc/init.d/oracleasm deletedisk RECOC2

/etc/init.d/oracleasm deletedisk RECOC3

3-Add re-create RECOC* disks

oracleasm createdisk RECOC1 /dev/sdd1;

oracleasm createdisk RECOC2 /dev/sdh1;

oracleasm createdisk RECOC3 /dev/sdj1;

ora-15032

if flashback on, you have to off it on your oracle database and use the grid user for below processes.

  1. On GUI–>open asmca—>Disk Group Name:RECOC1  select 3  disks to add diskgroup
  2. check your alert log again.

SUCCESS: diskgroup RECOC1 was mounted
Wed Feb 15 15:46:30 2017
SUCCESS: CREATE DISKGROUP RECOC1 EXTERNAL REDUNDANCY DISK ‘/dev/oracleasm/disks/RECOC1’ SIZE 102398M ,
‘/dev/oracleasm/disks/RECOC2’ SIZE 1048570M ,
‘/dev/oracleasm/disks/RECOC3’ SIZE 511993M ATTRIBUTE ‘compatible.asm’=’12.1.0.0.0′,’au_size’=’1M’ /* ASMCA */
Wed Feb 15 15:46:30 2017

 

root user SSH Failed Login Attempts on Oracle Exadata

Problem:root user SSH Failed Login Attempts on Oracle Exadata

Solution: check log file and unlock user

[root@exa01dbadm01 ~]# tail -f /var/log/secure

Jan 20 08:12:02 exa01dbadm01 sshd[119402]: Failed password for root from 172.18.17.71 port 61446 ssh2

Jan 20 08:12:14 exa01dbadm01 sshd[119402]: pam_tally2(sshd:auth): user root (0) tally 23, deny 5

[root@exa01dbadm01 ~]# pam_tally2 –user=root

Login           Failures Latest failure     From

root               23    01/20/17 09:12:14 172.18.17.71

[root@exa01dbadm01 ~]# pam_tally2 –user=root –reset

Login           Failures Latest failure     From

root               23    01/20/17 09:12:14 172.18.17.71

[root@exa01dbadm01 ~]# pam_tally2 –user=root

Login           Failures Latest failure     From

root                0