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--- faq:centos [2010/02/06 23:22]
219.218.55.4 PscTHOWGO
+++ faq:centos [2014/06/28 00:57] (current)
@@ Line 1: / Line 1: @@
-uX6cgS  <a href="http://nhvmrvkyihno.com/">nhvmrvkyihno</a>, [url=http://orbtnfwayyri.com/]orbtnfwayyri[/url], [link=http://fzxvirdtszxx.com/]fzxvirdtszxx[/link], http://wtoziybpeunn.com/
+===== Question:Restore a dump onto an empty hard disk =====
+Answer: Use restore rf dumpfilename
+Want to make a "ghost" of a linux / fedora / centos / redhat EL system that used Logical Volumes. By using the dump utility and restore it is possible to transfer all the contents of a hard disk to another one of a different size etc... dd might also do this but may be a bit tricky if the disks are different sizes.
+The major issue is keeping all the disk labels and logical volume and group names the same to avoid having to edit the /etc/fstab
+To restore a dump of a working Centos / Redhat EL - linux OS onto a new drive / machine
+Assuming the default redhat partitioning of
+  /dev/VolGroup00/LogVol00 /                       ext3    defaults        1 1
+  LABEL=/boot             /boot                   ext3    defaults        1 2
+=== 1 Make the dumps (one for each partition) ===
+dump 0fj mynewdumpfile /
+dump 0fj mynewdumpfileboot /boot
+transfer them to somewhere the new system will be able to access (USB External drive)
+=== 2 Boot the new system / drive from rescue disk ===
+<code>
+# fdisk the new drive
+#
+#eg 3 partitions , boot, root, swap
+# set types as Linux EXT2, Linux LVM , Linux Swap
+</code>
+<code>
+# for the boot one
+mke2fs -j /dev/hda1
+e2label /dev/hda1 /boot
+mkdir /mnt/boot
+mount /dev/hda1 /mnt/boot
+cd /mnt/boot
+restore rvf mynewdump.boot
+</code>
+<code>
+# for the root partition - a bit trickier - need to make the lvm stuff as well
+mkdir /mnt/root
+# create the physical volume
+lvm pvcreate /dev/hda2
+# display it with size
+lvm pvscan
+# create the volume group  - assign pv to it
+lvm vgcreate VolGroup00 /dev/hda2
+# create the logical volume - must specify size
+lvm lvcreate VolGroup00 -n LogVol00 -L 37G
+# just in case its not active
+lvm vgchange -ay
+#If you reboot and lose the lvm settings / devices  you may need to do these command to get the /dev/mapper devices made
+lvm lvscan
+lvm vgchange -ay
+lvm vgmknodes -v
+# the commands lvm vgcfgbackup -f filename
+# and  lvm vgcfgrestore -f filename
+# MAY be useful - not sure if they save doing all the create commands above ?
+# no they dont seem to do anything useful - they reference the PV uuid so if that is recreated the restore wont match anything  !
+# probably useful if it is a more sophisticated lv - with stripes etc...
+# now make the fs
+mke2fs -j /dev/mapper/LogVol00-VolGroup00
+# restore the dump from the USB drive or whatever
+mount /dev/mapper/LogVol00-VolGroup00 /mnt/root
+cd /mnt/root
+restore rvf mynewdump
+</code>
+<code>
+#write the grub boot stuff mbr etc
+umount /mnt/boot
+mount /dev/hda1 /mnt/root/boot
+grub-install --root-directory=/mnt/root  /dev/hda
+# cant find dev if you do this, it seemed like a good idea  ! chroot /mnt/root
+exit
+# now reboot it - it will do a fsck on the new partition - probably a good thing
+</code>
+If have trouble manually loading kernel and init from grub at boot fixed it for me - then once system is booted just do grub-install /dev/hda again and it will be ok.
+Mine stopped at grub 1.5 - but I didnt do the chroot grub-install  correctly - might try it again today just to see. Second attempt following above worked fine
+lvm and lots of other good stuff at http://dailypackage.fedorabook.com/index.php?/archives/159-System-Recovery-Week-Using-LVM-In-Rescue-Mode.html
+===== Question:Centos 4 Installation =====
+//Sat, 09 Apr 2005 00:49:12 +1000//
+Downloaded Centos 4 and created CDroms
+Installed onto Pentium III 800, 128 Megs RAM. 14 Gig hard disk
+Chose WORKSTATION installation.
+then used security settings in X to allow web,smtp,ssh, port 177 UDP
+Then to allow Cygwin remote X desktop had to edit /etc/X11/gdm/gdm.conf
+uncommented two lines
+<code>
+RemoteGreeter=/usr/bin/gdmlogin
+</code>
+change false to true
+<code>
+[Xdmcp]
+Enable=true
+</code>
+For chooser function (when using multiple X servers) can add
+<code>
+[chooser]
+Hosts= 192.168.54.3
+</code>
+restart X to get option
+Configured fetchmail to get emails, made local accounts and set forwarding rules. (copied fetchmail scripts from old server /etc/fetchmail.rc and /etc/rc.d/init.d/fetchmaild
+added custom lines to .bashrc
+<file>
+alias l="ls -altr"
+alias pg=more
+alias r="fc -s"
+</file>
+Download and install
+webmin
+From CENTOS CD install
+SAMBA  - copy config over and make directories
+/etc/samba/smbusers
+<code>
+apache = list of usernames
+</code>
+/etc/samba/smbconfig
+install apache (httpd package - edit /etc/httpd/conf/httpd.conf to change port)
+(Remember to open the firewall for each of these things !!!)
+Install squirrelmail and dovecot (dovecot does IMAP and POP) squirrelmail links into web for webmail.
+install named (bind)
+download and install dokuwiki, restore funstuff, check permissions.
+Copy over root scripts, add to cron for backup etc...
+Setup for rsync, firewall set so only local hosts can access (just in case)
+<file>
+# cat /etc/rsyncd.conf
+  [rsync]
+    path = /
+    use chroot = no
+    max connections = 4
+    auth users = root
+    secrets file = /etc/rsyncd.secrets
+    uid = root
+    gid = root
+</file>
+rsyncd.secrets stores username/password used for sync, then on 2nd server run
+<code>
+rsync -vx --password-file=/root/bin/jetcentos.passwd -az jetcentos::rsync/ /mnt/volgroup00/
+</code>
+where jetcentos.passwd stores matching password pair
+=== CENTOS 5 ===
+gdm.conf no longer there - now edit
+File now in  /etc/gdm/custom.conf
+<file>
+[security]
+AllowRoot=true
+AllowRemoteRoot=true
+[xdmcp]
+Enable=true
+</file>
+==== second install notes ====
+Then installed 2nd server, (twice - once in same partition structure as master once into second partition - just to create the partitions) and then made 2nd partition boot and used rsync to make first partition copy of real running server, have offline backup of real server. Needed to edit the fstab file after sync so that the mirror version boots with correct partitions, also needed to add extra entry to grub.conf. After updating mirror systems mirroring OS had to make copy of boot files from older version so it would boot.
+didnt include kernel source and then wanted to add it BUT the levels of dependencies had me frustated then realised that by using the --aid option to rpm to automatically install dependencies (and making a link so my copies of the rpms was in the right place) and it just did it.
+I had copied all the rpms over to /var/local/rpms
+<code>
+ mkdir -p /home/buildcentos/CENTOS/en/4.0/i386/CentOS
+ ln -s /var/local/rpms  /home/buildcentos/CENTOS/en/4.0/i386/CentOS/RPMS
+ rpm -i -aid  ../kernel-sourcecode-2.6.9-5.0.3.EL.noarch.rpm
+</code>
+===== Question:Upgrading from Fedora RC1 to CENTOS =====
+Answer: Tried using yum, in the end used CD's
+Wanted to upgrade a system from Fedora RC1 to Centos 4 - ideally wanted to have a way of doing over the net for remote upgrade but no luck on that yet.
+Boot of CENTOS cd1 - choose linux upgradeany (not listed anywhere as an option but found reference to it on fedora.org)
+This upgraded all packages but didnt add any new ones that I could see. Then tried to get YUM to work but even after swapping yun.conf still got reference to null NULL as the distribution
+<code>
+baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
+resolved to
+http://mirror.centos.org/centos/Null/os/
+This meant that got error 404
+</code>
+The $releasever variable was being set to Null rather than 4 - worked out that the package missing was centos-release-4-0.1
+so downloaded (hacked yum repo to hard code 4 and then chose did a yum install centos-release) and installed that package. Then put repos file back as defautl and did yum update seems to be working.
+then wanted to updater clamav - needed to follow instructions at
+http://crash.fce.vutbr.cz/yum-repository.html
+then edit repos file to put 3 as version number !
+then yum update clamav worked !
+===== Question:Sendmail - root mail not masqueraded =====
+Answer: Exposed user
+Comment out
+EXPOSED_USER(`root')dnl
+fixes it
+Set to Masquerade
+<code>
+MASQUERADE_AS(`mydomain.com')dnl
+dnl #
+dnl # masquerade not just the headers, but the envelope as well
+dnl #
+FEATURE(masquerade_envelope)dnl
+dnl #
+dnl # masquerade not just @mydomainalias.com, but @*.mydomainalias.com as well
+dnl #
+dnl FEATURE(masquerade_entire_domain)dnl
+dnl #
+</code>
+===== Question:Script to download a test file. Log the speed =====
+cat test_speed.sh
+<code>
+#/bin/sh
+#
+# script to download a test file and record the speed
+#
+cd /tmp
+wget --delete-after -o tmp1.log http://www.nano-tera.com.au/public/dokuwiki/media/cef_dokuwiki-2005-02-18.tgz
+grep " saved " tmp1.log >> /var/log/testspeed.log
+rm tmp1.log
+</code>
+===== Question:rpm --aid option where does it get the suggested files =====
+<code>
+rpm -i --aid package
+</code>
+Perhaps the --aid switch is a redhat only thing ?
+using centos or other new redhat/linux distributions rpm has the option aid --aid for automatically install dependents I assume. This seems great that any package that wont install because of failed dependencies can be installed as the rpm program will find the needed suggested packages.
+I needed this when after install centos we wanted to add X windows and Gnome but the number of dependencies was a bit daunting. But using the --aid switch and pointing it at a location containing all the rpms shipped with the system meant that once we had almost any X package installed we should have a running GUI system.
+But it expects it to be in an "unusual" location. I suspect it also looks in the current directory.
+To change the location it will install the packages from your need to change this file
+/etc/rpm/macros.solve
+<file>
+%_solve_pkgsdir /home/buildcentos/CENTOS/en/4.0/i386/CentOS/RPMS/
+</file>
+put the location that you keep your rpms (I tend to copy them into /var/rpms so I dont need to find the CD again, and then any I download go in /var/rpms/download
+to help this be found by someone who it bothers !!!
+What seemed like a long google search finally found a posting at http://groups.yahoo.com/group/rpm-list/message/22158 that explained it. I thought a posting with the key words of rpm package aid --aid (not sure how to search for -- in google) package dependencies rpm aid it will usually suggest the package(s) need to resolve the dependency default location for packages rpm install aid automatic install depencies dependency
+===== SAMBA and Active directory =====
+A good howto here http://www.enterprisenetworkingplanet.com/netos/article.php/3487081
+<code>
+	 cd /tmp
+	 rpm -qa > rpmlist.txt
+	 grep krb rpm8
+	 grep krb rpm*
+	 man yum
+	 yum list all > yum_lis_al.txt
+	 grep krnb yum_lis_al.txt
+	 grep krb yum_lis_al.txt
+	 cd /usr/sbin
+	 smbd -b | grep LDAP
+	 smbd -b | grep KRN
+	 smbd -b | grep KRB
+	 smbd -b | grep ADS
+	 smbd -b | grep WINBIND
+	 cd /tmp
+	 vi /etc/krb5.conf
+	 kinit adminusername
+         klist -e
+	 vi /etc/samba/smb.conf
+	 testparm
+	 service smb restart
+	 service winbind restart
+	 net ads join -U administrator
+	 vi /etc/nsswitch.conf
+	 service smb stop
+	 service winbind stop
+	 service winbind start
+	 service smb start
+	 wbinfo -g
+	 wbinfo -u
+	 getent passwd
+</code>
+http://www.flatmtn.com/computer/Linux-SquidNT.html
+smb.conf
+add line for debug logging
+  log level = 1
+==== Squid and ntlm ====
+<code>
+### JET 2008 problem with ntlm
+auth_param ntlm program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-ntlmssp -d=3 -l=/var/log/samba/ntlm_auth
+auth_param ntlm children 30
+auth_param basic children 5
+auth_param ntlm max_challenge_reuses 0
+auth_param ntlm max_challenge_lifetime 2 minutes
+auth_param basic program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-basic -d=1 -l=/var/log/samba/ntlm_auth
+external_acl_type ntgroup_helper %LOGIN /usr/lib/squid/wbinfo_group.pl
+acl proxyfullaccess external ntgroup_helper DOMAIN\ALLOW-INTERNET-ACCESS
+http_access allow all proxyfullaccess
+</code>
+Good guide here - http://mkeadle.org/index.php?p=13
+<file>
+Problem with winbind
+  winbindd version 3.0.10-1.4E.9 started.
+  Copyright The Samba Team 2000-2004
+[2008/09/12 01:15:52, 0] tdb/tdbutil.c:tdb_log(725)
+  tdb(/var/cache/samba/winbindd_idmap.tdb): rec_read bad magic 0x42424242 at offset=44656
+[2008/09/12 01:15:52, 0] nsswitch/winbindd_util.c:winbindd_upgrade_idmap(983)
+  Upgrading winbindd_idmap.tdb from an old version
+failed to copy /var/cache/samba/winbindd_idmap.tdb
+[2008/09/12 01:15:52, 0] nsswitch/winbindd_util.c:winbindd_upgrade_idmap(989)
+  Could not backup idmap database
+[2008/09/12 01:15:52, 1] nsswitch/winbindd.c:main(897)
+  Could not init idmap -- netlogon proxy only
+fixed by removing all samba cache
+</file>
+think problem was with ** /var/cache/samba/winbindd_idmap.tdb **
+<code>
+[root@proxy2 samba]# cd /var/cache/samba
+[root@proxy2 samba]# l
+total 152
+drwxr-xr-x  11 root root   4096 Nov 15  2006 ..
+drwxr-xr-x   4 root root   4096 Sep 12 01:19 old
+-rw-r--r--   1 root root   8192 Sep 12 01:19 winbindd_idmap.tdb
+-rw-r--r--   1 root root   8192 Sep 12 01:19 gencache.tdb
+-rw-------   1 root root   8192 Sep 12 01:21 share_info.tdb
+-rw-------   1 root root   8192 Sep 12 01:21 registry.tdb
+drwxr-xr-x   2 root root   4096 Sep 12 01:21 printing
+-rw-------   1 root root   8192 Sep 12 01:21 ntprinters.tdb
+-rw-------   1 root root    696 Sep 12 01:21 ntforms.tdb
+-rw-------   1 root root   8192 Sep 12 01:21 ntdrivers.tdb
+-rw-------   1 root root   8192 Sep 12 01:21 group_mapping.tdb
+-rw-------   1 root root   8192 Sep 12 01:29 netsamlogon_cache.tdb
+-rw-------   1 root root    696 Sep 12 01:29 messages.tdb
+-rw-------   1 root root  20172 Sep 12 01:29 winbindd_cache.tdb
+-rw-r--r--   1 root root    696 Sep 12 01:29 sessionid.tdb
+-rw-r--r--   1 root root    696 Sep 12 01:29 locking.tdb
+-rw-r--r--   1 root root   8192 Sep 12 01:29 connections.tdb
+-rw-r--r--   1 root root    696 Sep 12 01:29 brlock.tdb
+drwxr-x---   2 root squid  4096 Sep 12 01:29 winbindd_privileged
+-rw-r--r--   1 root root   8192 Sep 12 01:29 unexpected.tdb
+-rw-r--r--   1 root root    156 Sep 12 01:30 browse.dat
+</code>
+     kinit username@COM.AU
+     klist -e
+     klist -e
+     wbinfo -t
+     wbinfo -u
+     wbinfo -u
+     wbinfo -g

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