Move or Migrate User Accounts From Old Linux Server to a New Linux Server

4/20/13 Move or migrate user accounts from old Linux server to a new Linux server

www.cyberciti.biz/faq/howto-move-migrate-user-accounts-old-to-new-server/ 1/22

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Linux FAQ / Howtos

Move or migrate user accounts from old Linuxserver to a new Linux server

by nixCraft on December 13, 2006 83 comments last updated at August 16, 2007

Q. How do I Move or migrate user accounts to from old Linux server a new Cent OSLinux server including mails? This new system a fresh installation.

A. You can migrate users from old Linux server to new Linux sever with standard

commands such as tar, awk, scp and others. This is also useful if you are using old

Linux distribution such as Redhat 9 or Debian 2.x.

Following files/dirs are required for traditional Linux user management:

* /etc/passwd - contains various pieces of information for each user account

* /etc/shadow - contains the encrypted password information for user's accounts and optional the password

aging information.



* /etc/group - defines the groups to which users belong

* /etc/gshadow - group shadow file (contains the encrypted password for group)

* /var/spool/mail - Generally user emails are stored here.

* /home - All Users data is stored here.

You need to backup all of the above files and directories from old server to new Linux server.

Commands to type on old Linux system

First create a tar ball of old uses (old Linux system). Create a directory:

# mkdir /root/move/

Setup UID filter limit:

# export UGIDLIMIT=500

Now copy /etc/passwd accounts to /root/move/passwd.mig using awk to filter out system account (i.e. only

copy user accounts)# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/passwd >

/root/move/passwd.mig

Copy /etc/group file:

# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/group >

/root/move/group.mig

Copy /etc/shadow file:# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534) {print $1}' /etc/passwd

| tee - |egrep -f - /etc/shadow > /root/move/shadow.mig

Copy /etc/gshadow (rarely used):# cp /etc/gshadow /root/move/gshadow.mig

Make a backup of /home and /var/spool/mail dirs:# tar -zcvpf /root/move/home.tar.gz /home

# tar -zcvpf /root/move/mail.tar.gz /var/spool/mail

Where,

Users that are added to the Linux system always start with UID and GID values of as specified byLinux distribution or set by admin. Limits according to different Linux distro:

RHEL/CentOS/Fedora Core : Default is 500 and upper limit is 65534 (/etc/libuser.conf).Debian and Ubuntu Linux : Default is 1000 and upper limit is 29999 (/etc/adduser.conf).

You should never ever create any new system user accounts on the newly installed Cent OS Linux. Soabove awk command filter out UID according to Linux distro.

export UGIDLIMIT=500 - setup UID start limit for normal user account. Set this value as per yourLinux distro.awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/passwd >

/root/move/passwd.mig - You need to pass UGIDLIMIT variable to awk using -v option (it assignsvalue of shell variable UGIDLIMIT to awk program variable LIMIT). Option -F: sets the field

separator to : . Finally awk read each line from /etc/passwd, filter out system accounts and generatesnew file /root/move/passwd.mig. Same logic is applies to rest of awk command.

tar -zcvpf /root/move/home.tar.gz /home - Make a backup of users /home dirtar -zcvpf /root/move/mail.tar.gz /var/spool/mail - Make a backup of users mail dir



Use scp or usb pen or tape to copy /root/move to a new Linux system.# scp -r /root/move/* [email protected]:/path/to/location

Commands to type on new Linux system

First, make a backup of current users and passwords:

# mkdir /root/newsusers.bak

# cp /etc/passwd /etc/shadow /etc/group /etc/gshadow /root/newsusers.bak

Now restore passwd and other files in /etc/

# cd /path/to/location

# cat passwd.mig >> /etc/passwd

# cat group.mig >> /etc/group

# cat shadow.mig >> /etc/shadow

# /bin/cp gshadow.mig /etc/gshadow

Please note that you must use >> (append) and not > (create) shell redirection.

Now copy and extract home.tar.gz to new server /home

# cd /

# tar -zxvf /path/to/location/home.tar.gz

Now copy and extract mail.tar.gz (Mails) to new server /var/spool/mail

# cd /

# tar -zxvf /path/to/location/mail.tar.gz

Now reboot system; when the Linux comes back, your user accounts will work as they did before on old

system:# reboot

Please note that if you are new to Linux perform above commands in a sandbox environment. Abovetechnique can be used to UNIX to UNIX OR UNIX to Linux account migration. You need to make couple

of changes but overall the concept remains the same.

Further readings

Read man pages of awk, passwd(5), shadow(5), group(5), tar command

Updated for accuracy.

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{ 82 comments read them below or add one }

1 podee December 21, 2006 at 4:00 am

Hi

I followed your instuction on CentOS 4.4. When I reboot I lost my root user and gdm dint start.

I could login from all user but not root.Can you help to give me some advices please?

Pordee

Reply

2 nixcraft December 21, 2006 at 7:59 am

You made mistake somewhere. But dont worry you can login into single user mode (rescue mode)

and reset root account password.

http://www.cyberciti.biz/faq/linux-reset-forgotten-root-password/

Reply

3 ssdon January 2, 2007 at 10:25 pm

Great! The following line is probably a typo as Im assuming you mean to back this up with a copy,

otherwise you nuke the password files (probably what happened to nixcraft)

# mv /etc/passwd /etc/shadow /etc/group /etc/gshadow /root/newsusers.bak




Reply

4 nixcraft January 3, 2007 at 1:50 am

ssdon,

Typo has been fixed.

Appreciate your feedback.

Reply

5 Tom January 3, 2007 at 2:17 am

There is an error in the article. In the step where you back up the passwd, group, shadow, and

gshadow files from the new system to the newuser.bak directory, use the cp command, not mv.

In other words, the article should read:

Commands to type on new Linux system

First, make a backup of current users and passwords:# mkdir /root/newsusers.bak


Reply

6 Bud January 15, 2007 at 5:50 pm

Your instructions worked perfectly when migrating accounts from Redhat 4ES to another Redhat 4ES.

I added a couple of steps to move all the aliases and aliase folders to the new server. Thanks

Reply

7 Oduor Sam January 21, 2007 at 8:09 pm

Thanks,I am looking for a payrise after rescuing a dying server. It has worked for me perfectly.

Reply

8 Rick January 31, 2007 at 3:34 am

It may sound complicated, however, I am much more happy to do this with Linux than with

Mickey$oft O/Ss, in fact, I am much more happy to do ANYTHING with Linux over Windoze!

Reply

9 _ranger_ January 31, 2007 at 12:38 pm

If you had used LDAP for user accounts, then you wouldnt have needed to migrate user accounts .

Also, you could skip the whole tar aspect by just using rsync, e.g. rsync -e ssh -avtP /home/



newserver:/home

Reply

10 Charles Witt January 31, 2007 at 2:55 pm

Thanks for the howto. This is really close to what I have been looking for. In my particular situation

LDAP and NIS do not fit as well as your howto does. Also thanks for the comments of everyone, asthey are helpful.

Reply

11 exi February 5, 2007 at 1:14 pm

you might wanne consider runing sshfs on your new server, then u can login to the old (if sshd is

running) and simply copy the requierd data true fx. mc, and get all the file rights w you

its fast is simpel, and you only need to have secure shell intstalled on the old box`s to make it work

(and most boxses have ;)

just a littet advice for the data moving part.

Reply

12 Phil February 9, 2007 at 7:45 am

I have a problem, for starters, it look lie I was kind of doing the right thing myself but this blog really

helps, thanks. Anyway everything works fine untill I get to the bit where I am extraction all the users

data from the home.tar.gz. (kind of important bit) and it fails with text flying up the screen saying

Cannot change ownership to uid 511, gid 511 and Cannot mkdir: Permission denied and Cannotopen: Permission denied

obviously I do not have permissions :o(

I am loged in as root and the home directory of the new server has these permissions:

drwxrwxrwx 12 root root 0 Feb 8 19:28 home

Im not sure how it is possible to obtaim more permissions than that. I have tried with other privilages

on the home directory and it still does it.

PLease can someone help me

Many thanks

Phil

Reply

13 GT4NE1 February 14, 2007 at 6:06 pm

Dont forget about migrating cron jobs.

/var/spool/cron



Anything else we havent thought of?

Reply

14 aleksb April 17, 2007 at 9:45 am

Hi!

I tried your howto, and everything went along great until i rebooted and tried to log on with the users i

just copied over. root works fine. The passwords are not accepted, and i cannot change them with

passwd. passwd: Authentication token manipulation error. Im using fedora core 6.

Please help

Aleks

Reply

15 aleksb April 17, 2007 at 9:58 am

Nevermind, figured it out :)

Were missing a statement in the shadow file copy thingamabob

Reply

16 vikrant v mankar April 24, 2007 at 1:23 pm

hi i am new user in linux i am getting every answer from ur site.you are providing great solution on

every problem its being great to refer your site thanks for every thing

Reply

17 Subhanjan July 19, 2007 at 7:07 am

Hi,

I have a small query my new system already has couple of user accounts now I want to transfer the

user accounts from the old system I have checked both the systems there is no conflicts in UID,GID so

shall I go ahead with it.

Subhanjan

Reply

18 Subhanjan July 19, 2007 at 12:38 pm

Hi,

The things worked beautifully for me.

Thanks to the author.One more thing cant I script the steps that are done by the command awk?

Subhanjan

Reply



19 NewLinuxUser August 23, 2007 at 6:13 pm

I was able to migrate the home folders and accounts from RedHad Linx to Fedora but it seems that Icannot log in with the migrated accounts although I am able to see them under USERS. Am I missing

anything? Please help.

Reply

20 Prashantshant August 27, 2007 at 8:02 am

I am very much thankful that I got migration solution of user. How to transfer printer settings of each

user from one m/c to another? we have localy connected the printers to thin clients.

Reply

21 Paul Douglas Franklin September 19, 2007 at 6:30 pm

Thank you so much. This is beautiful. Im trying to upgrade to a new physical box, different distro,switch to ldap, and from Samba 2 to Samba 3. All this without messing up the working server. Ive

messed up the new box several times, and your migration page is very helpful in avoiding mistakes

during this stage. BTW, I used rsync instead of tar for the home directories.

Reply

22 asaguru October 10, 2007 at 10:40 am

now i am using centos 3 in a dell server now in that server i am running sendmail squid and iptables ftp

now i want to migrate the server in to new dell server running in centos 5

please any one help me on this issue

Reply

23 RaM October 30, 2007 at 8:51 am

hi

everyone i have question im a newbie admin can anyone give me advise or help me if how can i

backup my old linux email server III to new one or migrate to cent mail..tnx what are the important files

to back up for linux suse email server III?

Reply

24 Eliena Andrews November 27, 2007 at 10:12 am

hii,

i followed the procedure above, after all steps. USers password is not getting accepted, what could

have went wrong ?

Eliena Andrews

Reply

25 Kevin Smith December 24, 2007 at 10:28 pm



I cut and pasted the commands into an SSH terminal & checked the passwd.mig and shodow.mig to

find they were empty!

I double checked the lines and they were correct (values ect.)

Plus I end up with a file called - which Im guessing comes from the /etc/shadow line tee - (typomaybe?)

Id really like to get this working as it would be quite helpful with my project. My Level is slightly above

newbie Admin.

Kev

Reply

26 mj40 February 6, 2008 at 1:51 am

First of all i just wanna say thank you guys! This is my first time to get into the linux world! .

I follow the instruction regarding how tos .. then after rebooting my new centos5 box error message

appears:

The user database cannot be read. The problem is most likely caused by a mismatch between/etc/passwd and /etc/shadow or /etc/group and /etc/shadow. The program will exit now.

I follow the instructions twice and i got same message error. I dont know how to fix this one. Please

help me

Thanks.

Reply

27 Augusto February 19, 2008 at 8:34 pm

this how to works great :) But now Im stuck i need to migrate from Redhat to Debian the UGIDLIMIT

are different on this distros? any advice ?

thanks

Reply

28 Betty Harvey June 17, 2008 at 12:27 pm

Great instructions easy to follow!!! Worked like a charm!! Thanks for making this available I

have it bookmarked for when I do this again!

Reply

29 Peter Thomson June 18, 2008 at 1:49 am

RE: Augusto need to migrate from Redhat to Debian the UGIDLIMIT are different on this

distros

this advice would be useful for me too. Is it possible to adjust the /etc/passwd and /etc/group files?

Reply



30 Brett Knights June 26, 2008 at 5:38 pm

Thanks, This was very useful.

I needed to move a couple of system accounts

so did this:

awk -F: '($1 ~ /(tomcat|apache)/)' /etc/passwd > /root/move/passwd.mig

awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/passwd >>

/root/move/passwd.mig

and then couldnt figure out what the tee gave me and I was moving a set of users not based on UID

so did this:

awk -F: '{print $1}' /root/move/passwd.mig |egrep -f - /etc/shadow >

/root/move/shadow.mig

HTH

Reply

31 Debbie August 8, 2008 at 8:14 pm

Fabulous! Routine worked great! Thanks for posting it, saved me a ton of time.

Reply

32 Bryan August 26, 2008 at 4:34 pm

Also a couple of commands to check out if you are having problems with User database cannot be

read error: pwconv, grpconv and pwck. Works like a charm now :)

Reply

33 Miro October 16, 2008 at 6:16 pm

OK, I followed instructions got stuck with users not being able to log in. If instructions were not

correct, how do I fix it now?

Reply

34 Alan November 7, 2008 at 11:30 am

Excellent! I followed the instructions and did a fresh install of openSuse 11.0 on to 10.3. I have my old

/home on a separate partition and didnt mount it during install because Suse wants an initial user which

would have overwritten my original first user (UsId=1000). I installed, logged in as root, deleted the

initial user, changed the mount of /home to point to my old /home partition, did the transfer of backed

up passwd files etcetera, rebooted and bingo!

My only worry was, when it came to generating the initial user during install, I had a choice of

encryption algorithms for the password. Obviously if Id chosen the wrong one Id be stuck (though I

could probably log in as root and reset the users passwords).

So my question is: is it possible to tell what encryption algorithm was used for password storage before



starting?

Thanks again for the info.

Alan.

Reply

35 Dominic November 26, 2008 at 10:39 am

I am wanting to mirror users/groups to from one Ubuntu server to another. I see that Ubuntu starts off

with a user with UID 1000 (created with the name you give it in setup), I guess I should not try to

migrate this user since it already exists on the destination machine i.e. I should set UGIDLIMIT=1001?

What if one re-runs this action later to update the mirror? Do users gets duplicated cos surely one gets

multiple entries for same user in /etc/passwd?

Reply

36 Mike December 17, 2008 at 2:31 am

Great Doc. I was able to migrate a CentOS system to a VM.

Reply

37 Ganymede January 9, 2009 at 9:09 pm

My $0.02: For those who are concerned about UIDs and GIDs

you can change UIDs and GIDs on the old system before migration using:

groupmod -g (newgid) groupnameusermod -g (newgid) username OR usermod -G (newgid) username

(g changes the initial group or G to add an additional group membership)

Make a backup of the old files first and then change the group GID then change any appropriate users

attached to those groups if necessary. Test to make sure all is well. You can do this preemptively if youare going to from a system that starts custom groups at 500 to one that starts custom groups at 1000or if you dont want any UID/GID conflicts with your target system. Be the superuser and it would also

be prudent to make the changes while none of the users are attached.

Feel free to pick this post apart.

Reply

38 KPryor January 10, 2009 at 10:41 pm

Very very helpful. Im going to be needing to do this soon and didnt really know how to proceed.

Thanks!KP

Reply



39 Joe Riley February 5, 2009 at 8:19 am

Your FAQ fails to copy over /etc/passwd- as well

in the command:

cp /etc/passwd /etc/shadow /etc/group /etc/gshadow /root/newsusers.bak

should be:

cp /etc/passwd /etc/passwd- /etc/shadow /etc/group /etc/gshadow /root/newsusers.bak

Reply

40 Shawn February 17, 2009 at 4:16 pm

Fantastic instructions. A+++

Thanks.

Reply

41 gczman March 2, 2009 at 3:35 pm

copied the mboxs from one unix box and the /etc/passwd and /etc/shadow and it worked perfectly.thanks

Reply

42 waloyce March 24, 2009 at 4:26 am

Thanks the howto is very useful.But how to migrate the virtual users and domains accounts to a newserver

Reply

43 Denis March 30, 2009 at 5:07 am

Great instructions, worked well for me

BTW, if I had 2 linux servers, do you think it would be possible to merge the accounts into one of the2 ?

Reply

44 roshan April 6, 2009 at 10:30 am

your cp & awk command is so good

Reply

45 fidel April 23, 2009 at 10:44 am

thanks for this small & easy how-to



Worked like a charme

Reply

46 Juan Carlos June 15, 2009 at 2:30 pm

there is something similiar for Solaris ?

Reply

47 Vivek Gite June 15, 2009 at 2:49 pm

@Juan,

Solaris uses the same files /etc/passwd and friends. So it should work with a little modification.

Reply

48 mstone June 16, 2009 at 5:24 pm

Also check for aliases because a common multiple recipients solution uses that technique

Reply

49 Andy July 29, 2009 at 8:00 pm

If you use Samba shares; remember to grab /etc/samba/smb.conf, /etc/samba/smbusers, and/etc/samba/smbpasswd

Reply

50 John Wood April 1, 2010 at 3:51 pm

I was getting a - file created in /root/move when trying to get the shadow.mig, but Im not now, and

Im not sure what I did!

If anyone does get the - file, add some spaces around the tee command and try again Thatswhat I did and it went away!

Reply

51 John Wood April 1, 2010 at 3:55 pm

no, wait, I wasnt looking in the current directory I actually dont get rid of the - file

Reply

52 Lukas Johansson August 17, 2010 at 11:52 pm

Thanks for this guide, managed to migrate a large webserver without any major problem thanks toyou!

Reply



53 Embedded October 6, 2010 at 1:32 pm

Thanks for a great guide.

I have small problem with it.

From some reason the tar commands dont work under Red Hat Linux.it did not manage to tar or untar the files.

Do you know how to skip existing files?I tried -k flag but no success ;/

Reply

54 Ryan October 14, 2010 at 8:42 pm

Everything worked great. All my users & machines show up in User Manager.

However I cannot logon as a user, only root. It says wrong password.

Reply

55 Tim November 29, 2010 at 3:45 am

In Ubuntu, I had a problem following these instructions. When the screensaver was locked, youcouldnt unlock the screen without going to Switch User and then put in the password there. In

addition, half of the time your gdm session would immediately crash and youd have to log in fromscratch again.

The problem was that the shadow user wasnt able to read the /etc/shadow and /etc/gshadow files.The /etc/shadow and the /etc/gshadow files need to be chownd to root:shadow, and chmodd to 640like this:

# chown root:shadow /etc/shadow# chown root:shadow /etc/gshadow

# chmod 640 /etc/shadow /etc/gshadow

Reply

56 Irek May 13, 2011 at 4:16 pm

I tried to move account details from SUSE to Fedora/RH and password is not working :(I

Reply

57 Manojg August 1, 2011 at 11:09 pm

I created account successfully, can login but login take time and gives error:

/usr/bin/xauth: timeout in locking authority file /home/testuser/.Xauthority

Any help?

Reply



58 kaleeswari August 18, 2011 at 6:57 am

how to create the another root user and how to change the root ?

Reply

59 kaleeswari August 18, 2011 at 6:59 am

how to transfer the files from one root to another root user in same system using ubunto or fedora?

Reply

60 Chris September 26, 2011 at 6:07 pm

This worked perfect for me migrating users from an old FC3 box to a new Ubuntu 10.04 LTS one. Idid run into a problem when I tried to do it a second time. The instructions as they are will result induplicate entries in the /etc/passwd file. If you want to do this more than once, the *.mig files will need

some manual massaging before catting into the destination passwd file. (This may go without saying formost of you, but for me it wasnt something I thought of ahead of time). I was able to clean it up, but it

was a pain.

Reply

61 Frank Wang October 12, 2011 at 8:43 am

For the /etc/shadow file, better use following to prevent ambiguous match, say a local account nameddb will also match system account dbus

# awk -v LIMIT=$UGIDLIMIT -F: ($3>=LIMIT) && ($3!=65534) {print $1} /etc/passwd | sed -r -e s/(.*)/^\1:/ | egrep -f /etc/shadow > /root/move/shadow.mig

Reply

62 Paul December 11, 2011 at 8:50 pm

It worked perfect from FC 11 to FC 15. Btw, may I add the fact that the host keys must be

imported/ecported also. Reason: it is possible to have some users which are using their accounts(SFTP) with the help of an automaitc SFTP client. IN order to keep everything transparent for them,

the host keys of the machine must be imported/exported (etc/ssh).Maybe is better to test it and include it in this tutorial. Btw, the a lot for doing this.

Have a nice weekend.

Paul

Reply

63 Montaser Islam December 12, 2011 at 11:59 am

cool post;it save a lot of time man.

Reply



64 tem_dl April 5, 2012 at 3:24 am

cool tip. im using it. :D. tks so much

Reply

65 wfade April 19, 2012 at 8:21 am

oki think that you should awk at the new system for combine the new file that you had cp

Reply

66 AA April 25, 2012 at 12:55 pm

I am migrating accounts between an RHEL 5 server and RHEL 6 server and noticed that etc/gshadow

file entries for even the same group are listed differently between the two servers. For example: ntp:!::on rhel 6 and ntp:x:: on rhel 5. Your wonderful article shows that the gshadow file is copied in itsentirely (as is) from the old server to the new server. This means that the entries on the new server will

be completely replaced. Would it be better to append entries from the original gshadow that dontexist on the new server instead of replacing it with the entire file from the old server? Thanks in

advance.

Reply

67 Francisco Prez May 25, 2012 at 5:27 am

Gracias por su procedimiento:Solo una pequea sugerencia / pregunta:

No sera mejor en lugar de:

Copia el archivo / etc / gshadow (rara vez utilizada):# cp /etc/gshadow /root/move/gshadow.mig

Usar el mismo procedimiento que para shadow?:awk -v LIMIT=$UGIDLIMIT -F: ($3>=LIMIT) && ($3!=65534) {print $1} /etc/group | tee

|egrep -f /etc/gshadow > gshadow.mig

y ya en el nuevo servidor, en lugar de:

# /bin/cp gshadow.mig /etc/gshadow

hacer lo mismo que con los otros archivos:# cat gshadow.mig >> /etc/gshadow

Un saludo afectuoso..

Reply

68 ed June 10, 2012 at 9:38 pm

Great help!



Thanks

Reply

69 Steve Kelem June 26, 2012 at 10:18 pm

Francisco: (My Spanish is good enough to understand you, but not enough to answer)

Your script grabs every user name above UGIDLIMIT and then grabs every matching line fromgshadow.

1. If a user matches the UGID, and is in a group that already exists on the new machine, e.g., adm,disk, lp, man, dialout, lpadmin, then you get two entries for those groups in the new gshadow.

2. There is a small (but non-zero) chance that a users name is a substring of a group that doesntmatch UGID, then you would get false positives: roo, kern, hal, ack, kit, and other 3-letter initials thatsome users might (perhaps unwisely) use. The grep should check for lines with words that match

exactly the usernames.

Reply

70 mark July 8, 2012 at 8:54 pm

I keep getting permission denied when i attempt to create the shadow.mig ???

I added my user to the root group but no difference

-rw-r 1 root shadow 982 2012-04-19 13:28 shadow are my permission group has read

Reply

71 John August 22, 2012 at 4:02 pm

Wow, you know youve got a great tutorial when its copied verbatim by a bunch of others who dontgive one bit of credit to the original.

I have found this on at least 5 other sites with only ONE giving credit to Vivek and cyberciti.biz.

Reply

72 ian scott-fleming August 29, 2012 at 4:07 pm

Is there a reason you use !=65534 instead of =LIMIT) && ($3=LIMIT) && ($3



Great post! Thanks for this :-)

Reply

74 PhilipV October 19, 2012 at 2:50 am

I did it successfully. Thanks.

Reply

75 dali October 29, 2012 at 3:57 pm

think you..

Reply

76 Jeremy December 12, 2012 at 4:46 pm

I followed your instructions to migrate from redhat kernel 2.4 to centos 6 and for the most part, theyworked great. The only problem I am experiencing is when I go into the user manager I get the error I

couldnt find the numerical IDs of these groups: and it lists about 10 groups. (ident, mailnull, netdump,news, nscd, pcap, piranha, pvm, rpm, squid, xfs) I didnt see these groups in /etc/group or/etc/gshadow and I am not sure that any of the corresponding programs are loaded on the new

machine. Any help on this would be greatly appreciated. Thanks!

Reply


Correction. They are in /etc/gshadow but not in /etc/group

Reply


ahhhhhh. I answered my own question after re-reading my last post. All of the programs I listed had

GIDs lower than 500. I edited the the /etc/group file (vigr) and inserted the missing values. All is wellnow. Thanks for the awesome post.

Reply

79 metalmas January 1, 2013 at 9:17 am

Unfortunately this tutorial doesnt working when I tried migrate user with mailboxes from Fedora do

CentOS, because when I start postfix + dovecot a lot of error with permissions denied occured inmaillog and email klients could not connect :(

Reply

80 gamezat February 14, 2013 at 11:53 pm

thank you so much,

very useful i moved from server to anthor without any problems



thank you

Reply

81 ion March 1, 2013 at 2:35 pm

Thank you

Reply

82 ilde March 26, 2013 at 7:20 am

HiA very simple and effective approach, which I followed. Then, to copy all directories in /home

directory, I used next command as root:rsync -avz /home/ 192.168.0.15:/home

Where /home/ refers to the source machine, and 192.168.0.15 is the IP address of the destination one.All file permissions and ownerships were preserved. Also please make sure you include all slashesshown.

rsync must be installed in both the source and the destination boxes. Both machines are servers whichrun Debian Squeeze.

Thanks

Reply

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Tagged as: awk command, encrypted password, etc passwd, linux distribution, linux server, linux system, old server, scpcommand, tar ball, user account migration, user accounts

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Move or Migrate User Accounts From Old Linux Server to a New Linux Server