manually add dhcp server options

SUSE Product Topics SLES Configure-Administer
1

Hi,

We are moving from Netware DHCP servers to SLES 11 DHCP. How do I configure SLP settings with the standard SLES 11 SP1 DHCP Server?

Many thanks in advance.

Greetz,
Joost Brenters
CNV Netherlands

2

Hi Joost,

[QUOTE=joob;15334]Hi,

We are moving from Netware DHCP servers to SLES 11 DHCP. How do I configure SLP settings with the standard SLES 11 SP1 DHCP Server?

Many thanks in advance.

Greetz,
Joost Brenters
CNV Netherlands[/QUOTE]

as you’re not telling which way you’re trying: Probably best by manually adding the required options in /etc/dhcpd.conf

What options does your old server deliver to the client, that you need you new server to send? And how deep is your knowledge concerning DHCP (options, scopes,…), so that you’ll not be annoyed by “obvious” answers…?

Regards,
Jens

3

Thank you for your reply Jens,

I’m familiar with configuring SLES DHCP server via Yast. We are running Novell OES 11 on SLES 11 SP1 and currently we are offering dhcp service via Netware DNS/DHCP. But we want to move our DHCP from Netware to SLES 11 SP 1 servers. And in our options are currently 3, 6, 42, 78 and 79. Options 78 and 79 are SLP related (DA en scope addresses). In the Yast2 GUI we can provide the options 3, 6 and 42 via a pull-down menu. But options 78 and 79 are not available there.

Can I manually add these options in the GUI? Must I use the config files in /etc?

Hope this is a better way to ask my question…

Thanks,

Joost Brenters
CNV Netherlands

4

[QUOTE=joob;15342]Thank you for your reply Jens,

I’m familiar with configuring SLES DHCP server via Yast. We are running Novell OES 11 on SLES 11 SP1 and currently we are offering dhcp service via Netware DNS/DHCP. But we want to move our DHCP from Netware to SLES 11 SP 1 servers. And in our options are currently 3, 6, 42, 78 and 79. Options 78 and 79 are SLP related (DA en scope addresses). In the Yast2 GUI we can provide the options 3, 6 and 42 via a pull-down menu. But options 78 and 79 are not available there.

Can I manually add these options in the GUI? Must I use the config files in /etc?

Hope this is a better way to ask my question…

Thanks,

Joost Brenters
CNV Netherlands[/QUOTE]

Hi Joost,

a quick browse through the SLES docs didn’t show any obvious configuration menu for extra DHCP options, so you might actually need to specify these in dhcpd.conf or LDAP directly (we’re using separate configuration tools for this, so I’m not a primary info source for YaST’s capabilities :wink: ).

About setting slp-directory-agent and slp-service-scope in dhcpd.conf, I found a Novell article from 2007: http://www.novell.com/communities/node/1336/configure-slp-da-and-dhcp-send-option-78-79-oes-linux , which might give an extra hint on how to set the values in SLP and DHCP. Of course, there’s always the generic description in “man 5 dhcp-options”…

It’ll be a few days until I can access a SLES11 test system where I can check YaSTs support for these options, please let me know if I should do so.

And if anyone that can give some advice regarding the YaST configuration options reads this, please leave an answer for Joost!

Regards,
Jens

5

Jens,

Thanks for the info. I will set up a proper test environment and give the Novell article a try and report back the results in this thread.

Regards,

Joost Brenters
CNV Netherlands

6

On 20/08/2013 12:04, joob wrote:
[color=blue]

I’m familiar with configuring SLES DHCP server via Yast. We are running
Novell OES 11 on SLES 11 SP1 and currently we are offering dhcp service
via Netware DNS/DHCP. But we want to move our DHCP from Netware to SLES
11 SP 1 servers. And in our options are currently 3, 6, 42, 78 and 79.
Options 78 and 79 are SLP related (DA en scope addresses). In the Yast2
GUI we can provide the options 3, 6 and 42 via a pull-down menu. But
options 78 and 79 are not available there.[/color]

Since both OES11 and SLES11 SP1 have been mentioned are you looking to
move DHCP from NetWare to OES11 or SLES11 SP1?
[color=blue]

Can I manually add these options in the GUI? Must I use the config
files in /etc?[/color]

Which GUI are you talking about? YaST, iManager, or DNS/DHCP JavaConsole?

If using DHCP on OES11 then you should be administering it via DNS/DHCP
JavaConsole (iManager plug-in was deprecated).

HTH.

Simon
SUSE Knowledge Partner

Do you work with SUSE technologies at a university, college or school?
If so, your campus could benefit from joining the Technology Transfer
Partner (TTP) program. See TTP Organization | Micro Focus for more details.

7

[QUOTE=smflood;15354]On 20/08/2013 12:04, joob wrote:
[color=blue]

I’m familiar with configuring SLES DHCP server via Yast. We are running
Novell OES 11 on SLES 11 SP1 and currently we are offering dhcp service
via Netware DNS/DHCP. But we want to move our DHCP from Netware to SLES
11 SP 1 servers. And in our options are currently 3, 6, 42, 78 and 79.
Options 78 and 79 are SLP related (DA en scope addresses). In the Yast2
GUI we can provide the options 3, 6 and 42 via a pull-down menu. But
options 78 and 79 are not available there.[/color]

Since both OES11 and SLES11 SP1 have been mentioned are you looking to
move DHCP from NetWare to OES11 or SLES11 SP1?
[color=blue]

I’m moving DHCP from NetWare to SLES 11 SP1.

Can I manually add these options in the GUI? Must I use the config
files in /etc?[/color]

Which GUI are you talking about? YaST, iManager, or DNS/DHCP JavaConsole?

I’m talking about Yast. From a quick look it seems thast Yast reads the exact settings from the dhcp.conf file. So, that looks good.

If using DHCP on OES11 then you should be administering it via DNS/DHCP
JavaConsole (iManager plug-in was deprecated).

Thanks,
Joost Brenters
CNV Netherlands

8

[QUOTE=joob;15358]On 20/08/2013 12:04, joob wrote:
I’m moving DHCP from NetWare to SLES 11 SP1.[/QUOTE]

Hi Joost, while we’re at it: SP1 is outdated and without (standard) service - SP3 would be the current release, just in case you can influence this.

Regards,
Jens

9

Yes I know. But all our OES11 servers are SLES 11 SP1. We want to hold on to that standard. When all netware based services are migrated, we plan to upgrade our SLES servers…

Regards,
Joost

10

joob wrote:
[color=blue][color=green]

I’m moving DHCP from NetWare to SLES 11 SP1.[/color][/color]

Okay.
[color=blue][color=green]

I’m talking about Yast. From a quick look it seems thast Yast reads the
exact settings from the dhcp.conf file. So, that looks good.[/color][/color]

I’ve not used YaST to administer DHCP on SLES, instead preferring to edit
…conf files directly (and with DHCP on OES I manipulated DHCP objects in
eDirectory via LDAP).

I suspect YaST can handle editing the single /etc/dhcpd.conf file but not
any included files (which we use).

HTH.

Simon
SUSE Knowledge Partner

11

joob wrote:
[color=blue]

Yes I know. But all our OES11 servers are SLES 11 SP1. We want to hold
on to that standard. When all netware based services are migrated, we
plan to upgrade our SLES servers…[/color]

In the same vein as Jens’ comment re SLES11 SP1 I’ll note that OES11 is now
old and out of General Support with OES11 SP1 (on SLES11 SP2) recommended
to stay current - whilst SLES11 SP3 may now be available OES11 SP2 (which
will be only version of OES11 supported on SLES11 SP3) is due later this
year.

HTH.

Simon
SUSE Knowledge Partner

12

Hi,

Well, I followed the instructions in this article: “http://www.novell.com/communities/node/1336/configure-slp-da-and-dhcp-send-option-78-79-oes-linux” to setup a dhcp service on SLES11 SP1, in a vmware test environment, the firewall is turned off.

In the dhcpd.conf file slp options look like this:
option slp-directory-agent true ;
option slp-service-scope true “test-scope”;

On the win xp sp3 client I used slpinfo /a and it gives this output:

*** Novell Client for Windows NT ***
*** Service Location Diagnostics ***

SLP Version: 4.91.5.11
SLP Start Time: 1:43:54pm 8/21/2013
Last I/O: 1:52:44pm 8/21/2013
Total Packets: Out: 89 In: 8
Total Bytes: Out: 7276 In: 160

SLP Operational Parameters Values

Static Scopes NO
Static Directory Agents NO
Active Discovery YES
Use Broadcast for SLP Multicast NO
Use DHCP for SLP YES
SLP Maximum Transmission Unit 1400 bytes
SLP Multicast Radius 32 hops

SLP Timers Values

Give Up on Requests to SAs 15 seconds
Close Idle TCP Connections 5 minutes
Cache SLP Replies 1 minutes
SLP Default Registration Lifetime 10800 seconds
Wait Before Giving Up on DA 5 seconds
Wait Before Registering on Passive DA 1-2 seconds

Scope List Source(s)

DA IP Address Source(s) State Version Local Interface Scope(s)

Local Interface 192.168.228.130

Operational State: UP
Operating Mode(s): MCAST
SA/UA Scopes:
Last I/O: 1:52:44pm 8/21/2013
Total Packets: Out: 26 In: 1
Total Bytes: Out: 1902 In: 20
Last Addr Out: 224.0.1.22
Last Addr In: 192.168.228.128

So, as you can see, the slp settings are not visible on the client workstation. Am I missing something in the configuration settings on the dhcp server?

Thanks for any help on this one.

Regards,
Joost Brenters
CNV Netherlands

13

Hi Joost,

[QUOTE=joob;15416]Hi,

Well, I followed the instructions in this article: “http://www.novell.com/communities/node/1336/configure-slp-da-and-dhcp-send-option-78-79-oes-linux” to setup a dhcp service on SLES11 SP1, in a vmware test environment, the firewall is turned off.

In the dhcpd.conf file slp options look like this:
option slp-directory-agent true ;
option slp-service-scope true “test-scope”;[/QUOTE]

have you added these statements at the global level or in the scope of some subnet?

[QUOTE=joob;15416]On the win xp sp3 client I used slpinfo /a and it gives this output:

*** Novell Client for Windows NT ***
*** Service Location Diagnostics ***

SLP Version: 4.91.5.11
SLP Start Time: 1:43:54pm 8/21/2013
Last I/O: 1:52:44pm 8/21/2013
Total Packets: Out: 89 In: 8
Total Bytes: Out: 7276 In: 160

SLP Operational Parameters Values

Static Scopes NO
Static Directory Agents NO
Active Discovery YES
Use Broadcast for SLP Multicast NO
Use DHCP for SLP YES
SLP Maximum Transmission Unit 1400 bytes
SLP Multicast Radius 32 hops

SLP Timers Values

Give Up on Requests to SAs 15 seconds
Close Idle TCP Connections 5 minutes
Cache SLP Replies 1 minutes
SLP Default Registration Lifetime 10800 seconds
Wait Before Giving Up on DA 5 seconds
Wait Before Registering on Passive DA 1-2 seconds

Scope List Source(s)

DA IP Address Source(s) State Version Local Interface Scope(s)

Local Interface 192.168.228.130

Operational State: UP
Operating Mode(s): MCAST
SA/UA Scopes:
Last I/O: 1:52:44pm 8/21/2013
Total Packets: Out: 26 In: 1
Total Bytes: Out: 1902 In: 20
Last Addr Out: 224.0.1.22
Last Addr In: 192.168.228.128

So, as you can see, the slp settings are not visible on the client workstation. Am I missing something in the configuration settings on the dhcp server?

Thanks for any help on this one.

Regards,
Joost Brenters
CNV Netherlands[/QUOTE]

If you have no tool to check the DHCP replys of your server (i.e. on a Linux client you could use “dhcpcd-test” form the dhcpcd package, which would display all values from the dhcp reply), then you might at least check the server’s /var/log/messages for errors reported during startup of the dhcpd.

You have restarted the dhcpd on your server after changing the config file, haven’t you? Config file changes are only picked up by dhcpd at daemon start…

Regards,
Jens

14

Jens,

Yes, restarted the service after changes in de dhcpd.conf file… In /var/log/messages I see the dhcp service giving out an ip address. The slp settings are at the global level. I will install the “dhcpd-test” package… Didn’t know this one :wink:

Thanks,
Joost Brenters
CNV Netherlands

15

Hi Joost,

dhcpcd-test comes in very handy when you’re hunting dhcp configuration errors… we’re generating these config files, which leave a lot of room for potential problems :slight_smile: (even if the config file is ok, the transmitted reply may suffer from packet size limits - just to name one case that isn’t directly related to misgenerated files :smiley: )

Regards,
Jens

16

Hi Jens,

I’ve made the dhcp server authoritative for the configured subnet configured in the dhcpd.conf and now i’m getting the slp settings on the client. Don’t know the logic about that, but it seems to work! Here’s the full dhcpd.conf:

option domain-name “test.site”;
option domain-name-servers 192.168.228.128;
option routers 192.168.228.1;
option ntp-servers 192.168.228.128;
options nds-servers 192.168.228.128;
options slp-directory-agent true 192.168.228.128;
option slp-service-scope true “test-scope”;
default-lease-time 14400;
ddns-update-style none;
authoritative;
subnet 192.168.228.0 netmask 255.255.255.0 {
range 192.168.228.130 192.168.228.150;
default-lease-time 14400;
max-lease-time 172800;
}

And this is what I see on the client when I run slpinfo /a:

C:\>slpinfo /a

*** Novell Client for Windows NT ***
*** Service Location Diagnostics ***

SLP Version: 4.91.5.11
SLP Start Time: 1:43:54pm 8/21/2013
Last I/O: 4:18:33pm 8/21/2013
Total Packets: Out: 578 In: 37
Total Bytes: Out: 56286 In: 740

SLP Operational Parameters Values

Static Scopes NO
Static Directory Agents NO
Active Discovery YES
Use Broadcast for SLP Multicast NO
Use DHCP for SLP YES
SLP Maximum Transmission Unit 1400 bytes
SLP Multicast Radius 32 hops

SLP Timers Values

Give Up on Requests to SAs 15 seconds
Close Idle TCP Connections 5 minutes
Cache SLP Replies 1 minutes
SLP Default Registration Lifetime 10800 seconds
Wait Before Giving Up on DA 5 seconds
Wait Before Registering on Passive DA 1-2 seconds

Scope List Source(s)

DA
test-scope DHCP

DA IP Address Source(s) State Version Local Interface Scope(s)

192.168.228.128 DHCP INIT SLPV1 192.168.228.130

Local Interface 192.168.228.130

Operational State: UP
Operating Mode(s): MCAST,STATIC-DA,DHCP-MANDATORY-SCOPES
SA/UA Scopes: test-scope
Last I/O: 4:18:33pm 8/21/2013
Total Packets: Out: 9 In:
Total Bytes: Out: 396 In:
Last Addr Out: 192.168.228.128
Last Addr In: 0.0.0.0

Again, I don’t know why it works. But the dhcp server needs to be authoritative for the subnet is offering it’s addresses for.

Thanks,
Joost Brenters
CNV Netherlands

17

[QUOTE=joob;15424]Hi Jens,

I’ve made the dhcp server authoritative for the configured subnet configured in the dhcpd.conf and now i’m getting the slp settings on the client. Don’t know the logic about that, but it seems to work! Here’s the full dhcpd.conf:
[…]
Again, I don’t know why it works. But the dhcp server needs to be authoritative for the subnet is offering it’s addresses for.

Thanks,
Joost Brenters
CNV Netherlands[/QUOTE]

there’s an article about this situation at http://www.novell.com/support/kb/doc.php?id=7009129 , with the key sentence being “Typically, only the authoritative DHCP server will respond back to a multicast request. All non-authoritative DHCP servers will simply discard the request.”

This of course would mean that you should not have seen any reply without “authoritative”, or a different server might have responded (which would show in dhcpcd-test’s output - “info, eth0: offered 10.50.1.77 from 10.50.6.7 `yourserver.yourdomain.com’”).

Good to know the issue got cleared!

Regards,
Jens

18

Hi Joost & all,

for completeness’ sake a follow-up:

In the source code of dhcpd form ISC you will find that DHCPINFORM packets are ignored if the dhcpd is not authoritative for the corresponding subnet. I couldn’t find that in the manual page of dhcpd, which only mentions not sending DHCPNAK when the server isn’t configured as authoritative.

On the net, someone stated that when the dhcp server is not authoritative, some information is not passed out and that slp information is one of these bits of info. I couldn’t easily identify something like that in the source code, but that doesn’t mean that the statement is actually wrong.

Regards,
Jens