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hc_andy_35682
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Mar 03, 2010

Using TACACS+ on Big-IP LTM

Hi All,

 

 

I'm running BIG-IP LTM 6900 10.1.0.

 

 

I can't seem to get tacacs+ running for authentiation on the BIG-IP. I've followed the entry here by citizen_elah

 

 

http://devcentral.f5.com/Default.aspx?tabid=63&articleType=ArticleView&articleId=2316

 

 

Step 1:

 

 

On the BIG-IP shell, I've done this:

 

 

b remoterole role info adm '{

 

attribute "F5-LTM-User-Info-1=adm"

 

role administrator

 

user partition all

 

console enable

 

deny disable

 

line order 1

 

}'

 

 

I can see the above entry appearing in bigip.conf.

 

 

Step 2:

 

 

Then on the tacacs+ server I did this:

 

 

group = adm {

 

service = ppp protocol = ip {

 

F5-LTM-User-Info-1 = adm

 

}

 

}

 

 

user = user1 {

 

member = adm

 

login = cleartext "abc123"

 

}

 

 

And restarted the tacacs+ daemon.

 

 

Step 3:

 

 

I ran these commands on the BIG-IP shell.

 

 

b auth tacacs system-auth { debug enable secret mysecret service ppp protocol ip servers 210.15.x.x }

 

b system auth source type tacacs

 

 

But I can't login with the user1 and password abc123.

 

 

Troubleshooting

 

 

* Viewing the tac_plus.log file, I'm not seeing any key exchanges come in from the IP address of the BIG-IP.

 

 

* Connectivity seems to be ok. I can telnet to the tacacs+ server on port 49 from the BIG-IP.

 

 

[root@f5-2-manage:Standby] config telnet 210.15.x.x 49

 

Trying 210.15.x.x...

 

Connected to 210.15.x.x (210.15.x.x).

 

Escape character is '^]'.

 

 

* This is the log I see on the BIG-IP.

 

 

[root@f5-2-manage:Standby] config tail -f /var/log/secure

 

Mar 3 18:24:06 local/f5-2-manage notice httpd[27213]: 01070417:0: AUDIT - user admin - RAW: httpd(mod_auth_pam): user=admin(admin) partition=[All] level=Administrator tty=/bin/false host=172.16.53.253 attempts=1 start="Wed Mar 3 18:03:36 2010" end="Wed Mar 3 18:24:06 2010".

 

Mar 3 18:24:06 local/f5-2-manage notice httpd[27213]: pam_tacplus: user not authenticated by TACACS+

 

Mar 3 18:27:11 local/f5-2-manage err httpd[6296]: pam_tacplus: auth failed: Login incorrect

 

Mar 3 18:27:11 local/f5-2-manage alert httpd[6296]: pam_unix(httpd:auth): check pass; user unknown

 

Mar 3 18:27:11 local/f5-2-manage notice httpd[6296]: pam_unix(httpd:auth): authentication failure; logname= uid=48 euid=48 tty= ruser= rhost=172.16.51.52

 

Mar 3 18:27:13 local/f5-2-manage err httpd[6296]: [error] [client 172.16.51.52] AUTHCACHE PAM: user 'user1' - not authenticated: Authentication failure, referer: https://172.16.53.254/tmui/login.jsp?msgcode=1&

 

Mar 3 18:27:13 local/f5-2-manage info httpd(pam_audit)[6296]: User=user1 tty=(unknown) host=172.16.51.52 failed to login after 1 attempts (start="Wed Mar 3 18:27:11 2010" end="Wed Mar 3 18:27:13 2010").

 

Mar 3 18:27:13 local/f5-2-manage info httpd(pam_audit)[6296]: 01070417:6: AUDIT - user user1 - RAW: httpd(pam_audit): User=user1 tty=(unknown) host=172.16.51.52 failed to login after 1 attempts (start="Wed Mar 3 18:27:11 2010" end="Wed Mar 3 18:27:13 2010").

 

Mar 3 18:44:35 local/f5-2-manage notice httpd[6311]: 01070417:0: AUDIT - user admin - RAW: httpd(mod_auth_pam): user=admin(admin) partition=[All] level=Administrator tty=/bin/false host=172.16.53.253 attempts=1 start="Wed Mar 3 18:24:06 2010" end="Wed Mar 3 18:44:35 2010".

 

Mar 3 18:44:35 local/f5-2-manage notice httpd[6311]: pam_tacplus: user not authenticated by TACACS+

 

 

* Note the tacacs+ server is working fine for all our Cisco gear. Just can't get it working with the F5.

 

 

* Any ideas where I'm going wrong???

 

 

Thanks.

 

 

Andy

 

 

 

14 Replies

  • Is there any different configuration in two different model?

     

    i do not think there is.

     

  • And I'm also having the same issue, if anyone has come up with an answer. I've tried all the solutions above. The one that didn't make sense to me was setting the "member = adm". Well if that's the case, then I need to create a new TAC+ group. I have mine currently set to "member=admin" and the contents of the admin group:

     

    For f5 LTM 11.x and 10.x service = ppp protocol = ip { F5-LTM-User-Info-1 = adm }

     

    With the same settings setup in an Remote Role.

     

    I tried switching from PAM/LDAP to local DES logins, and that still didn't work.

     

    Apr 7 15:10:15 lb-foo err sshd[28512]: pam_tacplus: auth failed: Login incorrect Apr 7 15:10:15 lb-foo alert sshd[28512]: pam_unix(sshd:auth): check pass; user unknown Apr 7 15:10:15 lb-foo notice sshd[28512]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=192.168.1.1

     

  • I need to add this :

     

    pap = cleartext "abc123"

     

    THIS WORKS...

     

    But I don't want to use cleartext, I want to use PAM/LDAP on the backend. what are my options?

     

  • I solved this by adding "login = pam" into the tac_plus.cfg file and it works great.