Solaris Resources at Kempston
Configuring PPP dial-in on Solaris 7 and Solaris 8
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This page contains detailed step-by-step instructions to configure Solaris 7 and Solaris 8 for high-speed PPP dial-in, with the Solaris system acting as a PPP server. It doesn't cover connecting a Solaris system to an ISP where the Solaris system is dialling out; this is covered in Configuring PPP on Solaris to connect to an ISP.
If all you want is for the Solaris system to accept incoming modem calls and provide a terminal session to the calling computer, please see my page on Configuring high-speed dialup on Solaris. But configuring a PPP server provides more flexibility: it provides the calling computer with all the TCP/IP services available on the Solaris server, including the ability to run telnet, ftp and a Web browser as if it were part of the local network.
This page presents a detailed configuration process that should work first time if you follow it exactly. I've included a reasonable amount of explanation but, if you're interested in delving further into PPP, there's an excellent book on the subject by Andrew Sun entitled "Using and Managing PPP" published by O'Reilly, ISBN 1-56592-321-9.
Important Notes
The instructions assume that you have already configured your Solaris system for terminal mode dial-in as described in Configuring high-speed dialup on Solaris. It's essential that you do this first and ensure that remote systems can successsfully dial-in to your Solaris server, receive a login prompt, log in and run a terminal session. Unless this has been done first, configuring PPP dial-in as described on this page WILL NOT WORK. So, follow the instructions on that page first and then return here for details of the additional configuration needed to configure Solaris as a dial-in PPP server.
It's not necessary to have already configured your system to connect to an ISP. If you have done this, some of the steps on this page can be skipped and these are clearly noted. If you haven't configured your system to dial out to an ISP, this page is suffiicient to configure a PPP server, provided that you have terminal mode dial-in working.
Configuring PPP dial-in on Solaris
Please note that you must be logged in as root while implementing these instructions.
Skip this step if you have already configured dial-out PPP to connect to an ISP. Otherwise, check that the required packages have been installed:
# pkginfo | grep ppp
Check that (at least) the following are installed:
On Solaris 8:
system SUNWapppr PPP/IP Asynchronous PPP daemon configuration files system SUNWapppu PPP/IP Asynchronous PPP daemon and PPP login service system SUNWpppk PPP/IP and IPdialup Device Drivers
On Solaris 7:
system SUNWpppk Solstice PPP Device Drivers system SUNWapppu PPP/IP Asynchronous PPP daemon and PPP login service system SUNWapppr PPP/IP Asynchronous PPP daemon configuration files
If you have 64-bit Solaris 7 or 8 installed, you should also see the package:
system SUNWpppkx PPP/IP and IPdialup Device Drivers (64-bit)
If not, use pkgadd to install them in the order shown below.
For Intel (x86) Solaris 8:
Insert the CD marked "Solaris 8 Intel Platform Edition Software CD 2 of 2" and type:
# pkgadd -d /cdrom/sol_8_ia_2/Solaris_8/Product SUNWpppk # pkgadd -d /cdrom/sol_8_ia_2/Solaris_8/Product SUNWapppu # pkgadd -d /cdrom/sol_8_ia_2/Solaris_8/Product SUNWapppr
And for 64-bit Solaris 8:
# pkgadd -d /cdrom/sol_8_ia_2/Solaris_8/Product SUNWpppkx
For SPARC Solaris 8:
Insert the CD marked "Solaris 8 SPARC Platform Edition Software CD 2 of 2" and type:
# pkgadd -d /cdrom/sol_8_sparc_2/Solaris_8/Product SUNWpppk # pkgadd -d /cdrom/sol_8_sparc_2/Solaris_8/Product SUNWapppu # pkgadd -d /cdrom/sol_8_sparc_2/Solaris_8/Product SUNWapppr
And for 64-bit Solaris 8:
# pkgadd -d /cdrom/sol_8_sparc_2/Solaris_8/Product SUNWpppkx
For Intel (x86) Solaris 7:
Insert the Intel Solaris 7 CD and type:
# pkgadd -d /cdrom/sol_7_x86/s2/Solaris_2.7/Product SUNWpppk # pkgadd -d /cdrom/sol_7_x86/s2/Solaris_2.7/Product SUNWapppu # pkgadd -d /cdrom/sol_7_x86/s2/Solaris_2.7/Product SUNWapppr
And for 64-bit Solaris 7:
# pkgadd -d /cdrom/sol_7_x86/s2/Solaris_2.7/Product SUNWpppkx
For SPARC Solaris 7:
Insert the SPARC Solaris 7 CD and type:
# pkgadd -d /cdrom/sol_7_sparc/s0/Solaris_2.7/Product SUNWpppk # pkgadd -d /cdrom/sol_7_sparc/s0/Solaris_2.7/Product SUNWapppu # pkgadd -d /cdrom/sol_7_sparc/s0/Solaris_2.7/Product SUNWapppr
And for 64-bit Solaris 7:
# pkgadd -d /cdrom/sol_7_sparc/s0/Solaris_2.7/Product SUNWpppkx
If you happen to have the (commercial) server edition of Solaris 7 or Solaris 8, do not install the optional Solstice PPP product: it stops the bundled aspppd from working.
A common misconception is that an IP address is associated with a computer and this causes confusion when trying to understand how IP addresses are used on a dial-up link. More precisely, an IP address is associated with a network interface and one computer may have several network interfaces and hence several IP addresses.
Your Solaris system may be connected to a local network via a network interface card and ethernet, in which case it will already have an IP address associated with its existing network interface. Or it may be an isolated system without any network hardware installed. In both cases, at least two new IP addresses need to be chosen, one for the Solaris server end of the dial-up PPP link and one for the client end (the remote computer that dials up the Solaris server). It's important to understand that neither of these IP addresses are the same as any existing IP address associated with the Solaris server. We are about to add a new network interface (the dial-in PPP link) and need to choose two or more new IP addresses for each end of this link.
There are two situations to consider:
First, consider the case where your Solaris system is already connected to a local network. In this case, all of the new IP addresses for use with the PPP link must be on the same network as the existing ethernet network. You may have a block of public IP addresses assigned to your local network. If so, choose two unused IP addresses from that block for use with the PPP link. Or you may be using one of the reserved blocks of private IP addresses that anyone can use for isolated networks, such as the Class C block 192.168.1.0 to 192.168.1.255. In this case, choose two unused IP addresses from that block.
Secondly, consider the case where your Solaris system is a standalone machine, not networked to any other. In this case, I'd recommend choosing two IP addresses from the private Class C block mentioned above.
In the rest of these instructions, I'll assume that you've chosen 192.168.1.50 as the IP address of the Solaris server end of the PPP link and 192.168.1.51 as the IP address of the dialling up client end of the PPP link.
Two IP addresses are sufficient if only one person is ever going to make use of the dial-in PPP link. But if there will be more than one dial-in user, each user needs their own IP address. In this case, we could allocate an IP address of 192.168.1.51 to the first dial-in user, 192.168.1.52 to the second dial-in user, and so on.
Edit /etc/inet/hosts and add one line for the IP address to be associated with the server end of the dial-in PPP link and one line for each of the dialling-in clients. The hosts file associates a name with an IP address and I use the names ppp_server for the server end of the link and ppp_client1, ppp_client2, etc, for the client end. So the new lines to be added to /etc/inet/hosts read:
192.168.1.50 ppp_server # PPP dial-in server 192.168.1.51 ppp_client1 # First PPP dial-in client 192.168.1.52 ppp_client2 # Second PPP dial-in client 192.168.1.53 ppp_client3 # Third PPP dial-in client ...
You need to set up a user account on the Solaris system for each person who will connect using a PPP dialup. The names of these accounts can be anything you wish, as long as each one has a unique name. If someone needs to log in both as a local user and as a dial-in user, that person needs two user accounts. For example, I log in locally as mike and remotely over a dial-in link as mike-ppp.
The simplest way of setting up user accounts is by using admintool:
# admintool &
Select Users from the Browse menu and then Add from the Edit menu. Enter the chosen user name, such as mike-ppp in the User Name box and leave the User ID and Primary Group values unchanged unless you have a good reason to alter them. Type a descriptive string, conventionally the name of the user, in the Comment box. Alongside the Login Shell box, select Other, delete the string /bin/ and type:
/usr/sbin/aspppls
This is a replacement for the standard login shell and starts up PPP when the user has successfully logged in. Click on the button alongside Create Home Dir so that the button is pushed out and type /tmp in the Path box. Leave all the other fields unchanged and click on OK to create the user account. Admintool displays a message box reading "Home Directory is owned by a different user". Acknowledge this by clicking on OK (PPP dial-in users don't make any use of their home directory) and close admintool.
Set up a password for the new user account:
# passwd mike-ppp
and repeat for each of the users (if there are any more) who will need to dial-in using PPP.
If you haven't already set up dial-out PPP to an ISP, make two copies of /etc/asppp.cf:
# cp /etc/asppp.cf /etc/asppp.cf.original # cp /etc/asppp.cf /etc/asppp.cf.dialin
If you have already set up dial-out PPP to an ISP, you'll already have a file named /etc/asppp.cf.original, so just create the ".dialin" file:
# cp /etc/asppp.cf.original /etc/asppp.cf.dialin
Edit /etc/asppp.cf.dialin and add to the end of this file:
ifconfig ipdptp0 plumb ppp_server ppp_client1 up netmask + path ipcp_async_map 0 # Use async control character map 0 inactivity_timeout 0 # No inactivity timeout interface ipdptp0 # Use point-to-point interface 0 debug_level 9 # Full logging peer_system_name mike-ppp # Name of the dial-in user peer_ip_address ppp_client1 # IP address to be given to the client
If there will be more than one dial-in user, up to a maximum of 64 users, add another block to this file for each user. Each block should specify a different PPP device, ipdptp0 up to ipdptp63, a different dial-in user name and a different peer-ip-address. So, if there are two users who may dial-in, named Mike and Jane with user names of mike-ppp and jane-ppp, the lines added read:
ifconfig ipdptp0 plumb ppp_server ppp_client1 up netmask + path ipcp_async_map 0 # Use async control character map 0 inactivity_timeout 0 # No inactivity timeout interface ipdptp0 # Use point-to-point interface 0 debug_level 9 # Full logging peer_system_name mike-ppp # Name of the dial-in user peer_ip_address ppp_client1 # IP address to be given to the client ifconfig ipdptp1 plumb ppp_server ppp_client2 up netmask + path ipcp_async_map 0 # Use async control character map 0 inactivity_timeout 0 # No inactivity timeout interface ipdptp1 # Use point-to-point interface 1 debug_level 9 # Full logging peer_system_name jane-ppp # Name of the dial-in user peer_ip_address ppp_client2 # IP address to be given to the client
Note that each dial-in user is allocated a static IP address: in this example, mike-ppp is always allocated 192.168.1.51 and jane-ppp is always allocated 192.168.1.52.
When one system on a local network wants to communicate with another system on the same network, it needs to determine the MAC or ethernet address of the destination system. It does this by broadcasting an Address Resolution Protocol (ARP) request, asking for the owner of the destination IP address to respond with its MAC address. All TCP/IP communication with dial-in clients is handled by the Solaris server which routes packets to and from the clients so we need to arrange for the Solaris server to respond to ARP requests addressed to the dial-in clients by returning its own MAC address. This is done by setting up permanent entries in the ARP table on the server.
Note that this is necessary only if the Solaris server is connected to a network: skip this step if your Solaris machine isn't networked.
First, we need to determine the MAC address of the Solaris server:
# ifconfig -a | grep ether
This command returns the MAC address in the form:
ether 0:50:4:21:3c:80
although the MAC address of your Solaris system will differ from this example. Note this MAC address and provide it to the arp command as follows:
# /usr/sbin/arp -s ppp_client1 0:50:4:21:3c:80 pub
This needs to be done for each of the dial-in clients. So, for the second client (if you have one), type:
# /usr/sbin/arp -s ppp_client2 0:50:4:21:3c:80 pub
and so on, for each dial-in client. Remember to replace 0:50:4:21:3c:80 with the actual MAC address of your Solaris system.
The configuration completed so far allows a dial-in user to establish a PPP connection with the Solaris server and to access TCP/IP services on the server, such as telnet to log in, ftp to transfer files and http to connect to a Web server running on the Solaris box. But it doesn't allow the dial-in user to communicate beyond the Solaris server, perhaps to other machines on a local network. For this to work, we need to switch on IP forwarding in the Solaris kernel so that any packets from the dial-in user addressed to other machines are received on the ipdptp dial-in interface and forwarded out on to the local network. Similarly, packets reaching the Solaris server from the local network addressed to the dial-in IP address need to be forwarded out on the ipdptp interface. This is appropriate only if your Solaris server is networked, so skip this step if the Solaris machine isn't connected to a local network.
To switch on IP forwarding in the kernel, type:
# ndd -set /dev/ip ip_forwarding 1
It's important to note, at this point, that IP forwarding and proxy ARP settings do not survive a reboot. So, you need to ensure that IP forwarding and proxy ARP settings are re-established at boot time.
This is done by creating an initialisation script in the /etc/rc2.d directory. All script files in this directory that start with the characters "Snn", where "nn" are two numeric characters, are executed in the order implied by the value of "nn" whenever the system switches into multi-user mode and, in particular, as part of the system boot process.
Create a file in the /etc/rc2.d directory named S60dialin containing:
/usr/sbin/ndd -set /dev/ip ip_forwarding 1 /usr/sbin/arp -s ppp_client1 0:50:4:21:3c:80 pub
Then add another similar arp -s line for each additional dial-in client if more than one has been defined:
/usr/sbin/arp -s ppp_client2 0:50:4:21:3c:80 pub
replacing 0:50:4:21:3c:80 in each of the arp -s lines with the actual MAC address of your Solaris system as found in step 6 above.
Make the new script executable:
# chmod 744 /etc/rc2.d/S60dialin
This script file is executed automatically after the S47asppp script which starts the aspppd PPP daemon.
# touch /var/adm/log/asppp.log
This file is written to by the aspppd daemon and is invaluable for diagnosing errors in the configuration process. This file already exists if you have configured dial-out access to an ISP but doing a "touch" does no harm in any case.
The in.routed process may send routing information packets (RIP) on the dial-in link. This is undesirable and is prevented by creating a file named /etc/gateways containing the single line norip ipdptp0:
# echo "norip ipdptp0" > /etc/gateways
This should have been done already if you've configured your system for dial-out access to an ISP.
If you've defined more than one PPP client, create this file containing one line per dial-in client:
norip ipdptp0 norip ipdptp1 norip ipdptp2 ...
Open a new window and display the PPP log file:
# tail -f /var/adm/log/asppp.log
Copy /etc/asppp.cf.dialin to /etc/asppp.cf:
# cp /etc/asppp.cf.dialin /etc/asppp.cf
Stop and restart the asppp daemon which provides PPP services:
# /etc/init.d/asppp stop # /etc/init.d/asppp start
and check the PPP log file window for any errors reported during startup of the asppp daemon. If there are any syntax errors in the /etc/asppp.cf.dialin file, the PPP daemon will write an error message to the log file and probably exit. If startup succeeds, you should see something like:
20:15:07 Link manager (6374) started 21/12/99 20:15:07 parse_config_file: Successful configuration
in the log window.
Arrange for another system to dial-in to your Solaris system (there are notes further down this page on configuring Solaris and Windows to do this) and check that the dialling in system logs in successfully and establishes a PPP connection. When the remote system has made a connection, check that everything is working by using ping and telnet to the Solaris server and other systems on the local network (if any) and by running a Web browser on the remote system. If it doesn't work, the PPP log file will provide clues about what is wrong.
When you've tested the configuration and are satisifed that it's all working correctly, I recommend editing the /etc/asppp.cf.dialin file to reduce the logging level. A logging level of 9 causes every PPP packet to be logged to /var/adm/log/asppp.log and the log file can grow very large very quickly. I tend to use a logging level of 5 on my system:
debug_level 5 # Log all uucp chat script info
but you may like to experiment with the effect of various logging levels. Logging levels are defined in the man page for aspppd:
# man aspppd
If you wish to dial-out from the Solaris system to an ISP now and again but leave your system configured at other times to allow PPP dial-in, you will need to arrange for the dial-in version of /etc/asppp.cf to be present when the system boots, for the dial-out version to be present when you want to connect to an ISP and for the dial-in version to be re-instated when you disconnect from the ISP. If you've configured your system to dial-out to as ISP as described in Configuring PPP on Solaris to connect to an ISP, this can be achieved by some minor changes to the /dialup and /hangup scripts.
The /dialup script, which connects to your ISP, probably contains something like:
cp -p /etc/resolv.conf.isp /etc/resolv.conf cp -p /etc/asppp.cf.isp /etc/asppp.cf cp -p /etc/nsswitch.conf.dns /etc/nsswitch.conf /etc/init.d/asppp start /usr/sbin/ping 2.2.2.2
Edit this script file to stop the aspppd daemon before the dial-out version of /etc/asppp.cf is copied into place, to switch off IP forwarding and to delete the proxy ARP entries for your dial-in clients. After editing, your /dialup script should look something like:
/etc/init.d/asppp stop /usr/sbin/ndd -set /dev/ip ip_forwarding 0 /usr/sbin/arp -d ppp_client1 cp -p /etc/resolv.conf.isp /etc/resolv.conf cp -p /etc/asppp.cf.isp /etc/asppp.cf cp -p /etc/nsswitch.conf.dns /etc/nsswitch.conf /etc/init.d/asppp start /usr/sbin/ping 2.2.2.2
If you've defined more than one dial-in user, insert additional lines to delete the proxy ARP setting for each client in turn:
/usr/sbin/arp -d ppp_client1 /usr/sbin/arp -d ppp_client2 ...
Similar changes should be made to the /hangup script. Before editing this file, it probably reads:
/etc/init.d/asppp stop rm /etc/resolv.conf cp -p /etc/asppp.cf.original /etc/asppp.cf cp -p /etc/nsswitch.conf.files /etc/nsswitch.conf /usr/sbin/route -f
Edit the /hangup file so that it switches IP forwarding back on, defines the proxy ARP entries for your dial-in clients, re-instates the dial-in version of /etc/asppp.cf and restarts aspppd. After editing, your /hangup script should look something like:
/etc/init.d/asppp stop rm /etc/resolv.conf cp -p /etc/asppp.cf.dialin /etc/asppp.cf cp -p /etc/nsswitch.conf.files /etc/nsswitch.conf /usr/sbin/route -f /usr/sbin/ndd -set /dev/ip ip_forwarding 1 /usr/sbin/arp -s ppp_client1 0:50:4:21:3c:80 pub /usr/sbin/arp -s ppp_client2 0:50:4:21:3c:80 pub ... /etc/init.d/asppp start
Don't forget to insert one arp line for each PPP client defined in /etc/asppp.cf.dialin and to replace 0:50:4:21:3c:80 with the actual MAC address of your system.
That completes the configuration of Solaris for high-speed PPP dial-in.
If you've configured a Solaris system to act as a PPP dial-in server, you may want to configure another Solaris system to dial into the PPP server. The procedure for doing this is covered in Configuring PPP on Solaris to connect to an ISP. Although that page was written specifically to provide guidance on using a Solaris system to connect to an Internet Service Provider, the same principles apply when connecting to a Solaris system configured for PPP dial-in.
There are a few points to consider, however.
First, if the Solaris system to which you want to connect is a standalone system without an attached network, or is connected to a small network isolated from the wider Internet, it probably doesn't run, or have connectivity to, a DNS server. In this case, ignore the changes to /etc/resolv.conf and /etc/nsswitch.conf and omit the lines which copy these files in the /dialup and /hangup scripts. Instead, add lines to /etc/inet/hosts on the dialling-out system for the dial-in server itself and for each of the systems, if any, to which the server is networked. For example, if the dial-in server is named sunbeam and has an IP address of 192.168.1.1 and the server is networked to two other machines named sunray and sunshine, with IP addresses of 192.168.1.2 and 192.168.1.3, add the following lines to /etc/inet/hosts on the dialling-out machine:
192.168.1.1 sunbeam 192.168.1.2 sunray 192.168.1.3 sunshine
Secondly, /etc/asppp.cf on the dial-out machine can be configured for either a dynamic IP address, in which case the dial-in server will provide the real IP address as part of PPP negotiation, or for a fixed static IP address. If you decide to specify a fixed IP address, ensure that the address entered in /etc/asppp.cf matches the address allocated for that user on the dial-in machine.
Finally, the chat script in /etc/uucp/Systems on the dial-out machine should be defined for simple login / password authentication as in:
isp-ppp Any ACU 115200 telephone-number ogin: username word: password
and /etc/asppp.cf should not specify PAP or CHAP authentication. The dial-in server will switch to PPP only after the the incoming connection has identified itself as a PPP user and authenticated by responding to the Login: and Password: prompts. PAP and CHAP authentication are part of the PPP protocol and these methods of authentication are not available before PPP starts.
There's a small complication when configuring a Dial Up Networking connectoid on Windows 95 and 98 to make a PPP connection to a Solaris system. Windows DUN normally tries to authenticate using PAP or CHAP, does not respond to conventional login and password prompts and expects PPP to be running on the server as soon as a connection is made. Although Solaris PPP dial-in supports both PAP and CHAP, PPP itself is usually not started until after the incoming connection has authenticated using login and password prompts. The way round this dilemma is to configure Windows DUN to display a login dialogue box after connection as shown below. When you have this working, I'll show how to automate the login process using a script.
To configure a suitable DUN connectoid on Windows, double-click on My Computer, double-click on Dial-Up Networking and then double-click on Make New Connection. In the box labelled Type a name for the computer you are dialing, type a name, such as Solaris, to identify this connectoid and click on Next. Type the Area code and Telephone number of the modem attached to the Solaris dial-in system, click on Next and then on Finish.
You should now see a new connectoid in the Dial Up Networking folder labelled Solaris or whatever you called it. Right-click on this connectoid and select Properties. Click on the Server Types tab and untick Log on to network, Enable software compression, NetBEUI and IPX/SPX Compatible. The only box on this tab that should be ticked is TCP/IP. Now click on the TCP/IP Settings... button and ensure that Server assigned IP address and Server assigned name server addresses are selected. Also check that Use IP header compression and Use default gateway on remote network are ticked. Click on OK to return to the Server Types tab. Click on the General tab and click on the button under the modem name labelled Configure.... In the Modem Properties box that appears, click on the Options tab and tick Bring up terminal window after dialing. Finally, click on OK to dismiss the Modem Properties dialog box and click on OK again to close the DUN Properties dialog. The new DUN connectoid is ready for use.
To dial up the Solaris system, double-click on the new DUN connectoid. Ignore the User name and Password boxes (it doesn't matter what is entered here) and click on Connect. The modem should should dial out and make a connection with the modem on the Solaris machine. At this point, DUN displays a terminal window in which you should see the Login: prompt from the Solaris system. Type your user name, such as mike-ppp and respond to the Password: prompt and press ENTER on the keyboard. Then, click on Continue and Windows should start PPP, complete the negotiation and establish a PPP connection as it would if you were dialling up an ISP.
I strongly recommend that you test the dial-up connection using a terminal window as described above. When this is working, you may like to automate the login process using a script. Note that DUN scripting was introduced during the lifetime of Windows 95 and will not be present on early Windows 95 systems unless DUN has been upgraded.
First, create a text file using Notepad containing the following:
proc main waitfor "ogin:" transmit $USERID transmit "<cr>" waitfor "word:" transmit $PASSWORD transmit "<cr>" endproc
and save this as a file named, for example, c:\windows\solaris.scp. Note that the ".scp" suffix is important.
Then double-click on My Computer, double-click on Dial-Up Networking, right-click on the DUN connectoid and select Properties. Click on the Scripting tab and enter the name of the script file, such as c:\windows\solaris.scp in the box marked Script file File name. Return to the General tab and click on the button under the modem name labelled Configure.... In the Modem Properties box that appears, click on the Options tab and untick Bring up terminal window after dialing. Finally, click on OK to dismiss the Modem Properties dialog box and click on OK again to close the DUN Properties dialog.
To dial up the Solaris system using the new script, double-click on the DUN connectoid, enter your Solaris user name and password in the User name and Password boxes, tick the Save password box and click on Connect. The modem should dial out and establish a PPP connection without any user interaction.
Has this guide been useful?
I hope these instructions prove useful. If you have any comments or suggestions for improvement, or have found any technical errors, please email me at mike@kempston.net
This page is copyright © mike@kempston.net 2000. Reproduction is forbidden without the author's permission. You are welcome to link to these pages if you wish but please point to the pages at www.kempston.net: Solaris Resources at Kempston
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Last updated 11 February 2001