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diff --git a/docs/docbook/projdoc/Diagnosis.xml b/docs/docbook/projdoc/Diagnosis.xml new file mode 100644 index 0000000000..4856e24a46 --- /dev/null +++ b/docs/docbook/projdoc/Diagnosis.xml @@ -0,0 +1,557 @@ +<chapter id="diagnosis"> +<chapterinfo> + &author.tridge; + &author.jelmer; + &author.danshearer; + <pubdate>Wed Jan 15</pubdate> +</chapterinfo> + +<title>The Samba Checklist</title> + +<sect1> +<title>Introduction</title> + +<para> +This file contains a list of tests you can perform to validate your +Samba server. It also tells you what the likely cause of the problem +is if it fails any one of these steps. If it passes all these tests, +then it is probably working fine. +</para> + +<para> +You should do all the tests, in the order shown. We have tried to +carefully choose them so later tests only use capabilities verified in +the earlier tests. However, do not stop at the first error as there +have been some instances when continuing with the tests has helped +to solve a problem. +</para> + +<para> +If you send one of the Samba mailing lists an email saying, <quote>it does not work</quote> +and you have not followed this test procedure, you should not be surprised +if your email is ignored. +</para> + +</sect1> + +<sect1> +<title>Assumptions</title> + +<para> +In all of the tests, it is assumed you have a Samba server called +BIGSERVER and a PC called ACLIENT both in workgroup TESTGROUP. +</para> + +<para> +The procedure is similar for other types of clients. +</para> + +<para> +It is also assumed you know the name of an available share in your +&smb.conf;. I will assume this share is called <smbconfsection>tmp</smbconfsection>. +You can add a <smbconfsection>tmp</smbconfsection> share like this by adding the +lines shown in <link linkend="tmpshare"/>. +</para> + +<para><smbconfexample id="tmpshare"> +<title>smb.conf with [tmp] share</title> +<smbconfsection>[tmp]</smbconfsection> +<smbconfoption><name>comment</name><value>temporary files </value></smbconfoption> +<smbconfoption><name>path</name><value>/tmp</value></smbconfoption> +<smbconfoption><name>read only</name><value>yes</value></smbconfoption> +</smbconfexample> +</para> + +<note><para> +These tests assume version 3.0.0 or later of the Samba suite. +Some commands shown did not exist in earlier versions. +</para></note> + +<para> +Please pay attention to the error messages you receive. If any error message +reports that your server is being unfriendly, you should first check that your +IP name resolution is correctly set up. Make sure your <filename>/etc/resolv.conf</filename> +file points to name servers that really do exist. +</para> + +<para> +Also, if you do not have DNS server access for name resolution, please check +that the settings for your &smb.conf; file results in <command>dns proxy = no</command>. The +best way to check this is with <command>testparm smb.conf</command>. +</para> + + +<para> +<indexterm><primary>log files</primary><secondary>monitoring</secondary></indexterm> +It is helpful to monitor the log files during testing by using the +<command>tail -F log_file_name</command> in a separate +terminal console (use ctrl-alt-F1 through F6 or multiple terminals in X). +Relevant log files can be found (for default installations) in +<filename>/usr/local/samba/var</filename>. Also, connection logs from +machines can be found here or possibly in <filename>/var/log/samba</filename>, +depending on how or if you specified logging in your &smb.conf; file. +</para> + +<para> +If you make changes to your &smb.conf; file while going through these test, +remember to restart &smbd; and &nmbd;. +</para> + +</sect1> + +<sect1> +<title>The Tests</title> +<procedure> +<title>Diagnosing your Samba server</title> + + +<step performance="required"> +<para> +<indexterm><primary>testparm</primary></indexterm> +In the directory in which you store your &smb.conf; file, run the command +<command>testparm smb.conf</command>. If it reports any errors, then your &smb.conf; +configuration file is faulty. +</para> + +<note><para> +Your &smb.conf; file may be located in: <filename>/etc/samba</filename> +or in <filename>/usr/local/samba/lib</filename>. +</para></note> +</step> + +<step performance="required"> +<para> +Run the command <command>ping BIGSERVER</command> from the PC and +<command>ping ACLIENT</command> from the UNIX box. If you do not get a valid response, +then your TCP/IP software is not correctly installed. +</para> + +<para> +You will need to start a <quote>dos prompt</quote> window on the PC to run ping. +</para> + +<para> +If you get a message saying <quote><errorname>host not found</errorname></quote> or similar, then your DNS +software or <filename>/etc/hosts</filename> file is not correctly setup. +It is possible to run Samba without DNS entries for the server and client, but it is assumed +you do have correct entries for the remainder of these tests. +</para> + +<para> +Another reason why ping might fail is if your host is running firewall +software. You will need to relax the rules to let in the workstation +in question, perhaps by allowing access from another subnet (on Linux +this is done via the appropriate firewall maintenance commands <command>ipchains</command> +or <command>iptables</command>). +</para> + +<note> +<para> +Modern Linux distributions install ipchains/iptables by default. +This is a common problem that is often overlooked. +</para> +</note> + +<para> +If you wish to check what firewall rules may be present in a system under test, simply run +<command>iptables -L -v</command> or if <parameter>ipchains</parameter>-based firewall rules are in use, +<command>ipchains -L -v</command>. +</para> + +<para> +Here is a sample listing from a system that has an external ethernet interface (eth1) on which Samba +is not active, and an internal (private network) interface (eth0) on which Samba is active: +<screen> +frodo:~ # iptables -L -v +Chain INPUT (policy DROP 98496 packets, 12M bytes) + pkts bytes target prot opt in out source destination + 187K 109M ACCEPT all -- lo any anywhere anywhere + 892K 125M ACCEPT all -- eth0 any anywhere anywhere +1399K 1380M ACCEPT all -- eth1 any anywhere anywhere \ + state RELATED,ESTABLISHED + +Chain FORWARD (policy DROP 0 packets, 0 bytes) + pkts bytes target prot opt in out source destination + 978K 1177M ACCEPT all -- eth1 eth0 anywhere anywhere \ + state RELATED,ESTABLISHED + 658K 40M ACCEPT all -- eth0 eth1 anywhere anywhere + 0 0 LOG all -- any any anywhere anywhere \ + LOG level warning + +Chain OUTPUT (policy ACCEPT 2875K packets, 1508M bytes) + pkts bytes target prot opt in out source destination + +Chain reject_func (0 references) + pkts bytes target prot opt in out source destinat +</screen> +</para> + +</step> + +<step performance="required"> +<para> +Run the command: <command>smbclient -L BIGSERVER</command> +on the UNIX box. You should get back a list of available shares. +</para> + +<para> +If you get an error message containing the string <quote>Bad password</quote>, then +you probably have either an incorrect <parameter>hosts allow</parameter>, +<parameter>hosts deny</parameter> or <parameter>valid users</parameter> line in your +&smb.conf;, or your guest account is not valid. Check what your guest account is using &testparm; and +temporarily remove any <parameter>hosts allow</parameter>, <parameter>hosts deny</parameter>, +<parameter>valid users</parameter> or <parameter>invalid users</parameter> lines. +</para> + +<para> +If you get a message <quote><errorname>connection refused</errorname></quote> response, then the <command>smbd</command> server may +not be running. If you installed it in <filename>inetd.conf</filename>, then you probably edited +that file incorrectly. If you installed it as a daemon, then check that +it is running, and check that the netbios-ssn port is in a LISTEN +state using <command>netstat -a</command>. +</para> + +<note><para> +<indexterm><primary>inetd</primary></indexterm> +<indexterm><primary>xinetd</primary><see>inetd</see></indexterm> +Some UNIX/Linux systems use <command>xinetd</command> in place of +<command>inetd</command>. Check your system documentation for the location +of the control files for your particular system implementation of +the network super daemon. +</para></note> + +<para> +If you get a message saying <quote><errorname>session request failed</errorname></quote>, the server refused the +connection. If it says <quote>Your server software is being unfriendly</quote>, then +it's probably because you have invalid command line parameters to &smbd;, +or a similar fatal problem with the initial startup of &smbd;. Also +check your config file (&smb.conf;) for syntax errors with &testparm; +and that the various directories where Samba keeps its log and lock +files exist. +</para> + +<para> +There are a number of reasons for which smbd may refuse or decline +a session request. The most common of these involve one or more of +the &smb.conf; file entries as shown in <link linkend="modif1"/>. +</para> + + +<para> +<smbconfexample id="modif1"> + <title>Configuration for only allowing connections from a certain subnet</title> +<smbconfsection>[globals]</smbconfsection> +<member>...</member> +<smbconfoption><name>hosts deny</name><value>ALL</value></smbconfoption> +<smbconfoption><name>hosts allow</name><value>xxx.xxx.xxx.xxx/yy</value></smbconfoption> +<smbconfoption><name>interfaces</name><value>eth0</value></smbconfoption> +<smbconfoption><name>bind interfaces only</name><value>Yes</value></smbconfoption> +<member>...</member> +</smbconfexample> +</para> + +<para> +In the above, no allowance has been made for any session requests that +will automatically translate to the loopback adapter address 127.0.0.1. +To solve this problem, change these lines as shown in <link linkend="modif2"/>. +</para> + +<para> +<smbconfexample id="modif2"> + <title>Configuration for allowing connections from a certain subnet and localhost</title> +<smbconfsection>[globals]</smbconfsection> +<member>...</member> +<smbconfoption><name>hosts deny</name><value>ALL</value></smbconfoption> +<smbconfoption><name>hosts allow</name><value>xxx.xxx.xxx.xxx/yy 127.</value></smbconfoption> +<smbconfoption><name>interfaces</name><value>eth0 lo</value></smbconfoption> +<member>...</member> +</smbconfexample> +</para> + +<para> +<indexterm><primary>inetd</primary></indexterm> +Another common cause of these two errors is having something already running +<indexterm><primary>smbclient</primary></indexterm> +on port <constant>139</constant>, such as Samba (&smbd; is running from <application>inetd</application> already) or +something like Digital's Pathworks. Check your <filename>inetd.conf</filename> file before trying +to start &smbd; as a daemon &smbmdash; it can avoid a lot of frustration! +</para> + +<para> +And yet another possible cause for failure of this test is when the subnet mask +and/or broadcast address settings are incorrect. Please check that the +network interface IP Address/Broadcast Address/Subnet Mask settings are +correct and that Samba has correctly noted these in the <filename>log.nmbd</filename> file. +</para> + +</step> + +<step performance="required"> + +<para> +Run the command: <command>nmblookup -B BIGSERVER __SAMBA__</command>. +You should get back the IP address of your Samba server. +</para> + +<para> +If you do not, then nmbd is incorrectly installed. Check your <filename>inetd.conf</filename> +if you run it from there, or that the daemon is running and listening to udp port 137. +</para> + +<para> +One common problem is that many inetd implementations can't take many +parameters on the command line. If this is the case, then create a +one-line script that contains the right parameters and run that from +inetd. +</para> + +</step> + +<step performance="required"> + +<para> +Run the command: <command>nmblookup -B ACLIENT `*'</command> +</para> + +<para> +You should get the PC's IP address back. If you do not then the client +software on the PC isn't installed correctly, or isn't started, or you +got the name of the PC wrong. +</para> + +<para> +If ACLIENT does not resolve via DNS then use the IP address of the +client in the above test. +</para> + +</step> + +<step performance="required"> + +<para> +Run the command: <command>nmblookup -d 2 '*'</command> +</para> + +<para> +This time we are trying the same as the previous test but are trying +it via a broadcast to the default broadcast address. A number of +NetBIOS/TCP/IP hosts on the network should respond, although Samba may +not catch all of the responses in the short time it listens. You +should see the <quote><errorname>got a positive name query response</errorname></quote> +messages from several hosts. +</para> + +<para> +If this does not give a similar result to the previous test, then +nmblookup isn't correctly getting your broadcast address through its +automatic mechanism. In this case you should experiment with the +<smbconfoption><name>interfaces</name></smbconfoption> option in &smb.conf; to manually configure your IP +address, broadcast and netmask. +</para> + +<para> +If your PC and server aren't on the same subnet, then you will need to use the +<option>-B</option> option to set the broadcast address to that of the PCs subnet. +</para> + +<para> +This test will probably fail if your subnet mask and broadcast address are +not correct. (Refer to TEST 3 notes above). +</para> + +</step> + +<step performance="required"> + + +<para> +<indexterm><primary>smbclient</primary></indexterm> +Run the command: <command>smbclient //BIGSERVER/TMP</command>. You should +then be prompted for a password. You should use the password of the account +with which you are logged into the UNIX box. If you want to test with +another account, then add the <option>-U accountname</option> option to the end of +the command line. For example, <command>smbclient //bigserver/tmp -Ujohndoe</command>. +</para> + +<note><para> +It is possible to specify the password along with the username as follows: +<command>smbclient //bigserver/tmp -Ujohndoe%secret</command>. +</para></note> + +<para> +Once you enter the password, you should get the <prompt>smb></prompt> prompt. If you +do not, then look at the error message. If it says <quote><errorname>invalid network +name</errorname></quote>, then the service <smbconfsection>tmp</smbconfsection> is not correctly setup in your &smb.conf;. +</para> + +<para> +If it says <quote><errorname>bad password</errorname></quote>, then the likely causes are: +</para> + +<orderedlist> +<listitem> + <para> + You have shadow passwords (or some other password system) but didn't + compile in support for them in &smbd;. + </para> +</listitem> + +<listitem> + <para> + Your <smbconfoption><name>valid users</name></smbconfoption> configuration is incorrect. + </para> +</listitem> + +<listitem> + <para> + You have a mixed case password and you haven't enabled the <smbconfoption><name>password level</name></smbconfoption> option at a high enough level. + </para> +</listitem> + +<listitem> + <para> + The <smbconfoption><name>path</name></smbconfoption> line in &smb.conf; is incorrect. Check it with &testparm;. + </para> +</listitem> + +<listitem> + <para> + You enabled password encryption but didn't map UNIX to Samba users. Run: + <command>smbpasswd -a username</command> + </para> +</listitem> +</orderedlist> + +<para> +Once connected, you should be able to use the commands <command>dir</command>, <command>get</command>, +<command>put</command> and so on. Type <command>help command</command> for instructions. You should +especially check that the amount of free disk space shown is correct when you type <command>dir</command>. +</para> + +</step> + +<step performance="required"> + +<para> +On the PC, type the command <command>net view \\BIGSERVER</command>. You will +need to do this from within a dos prompt window. You should get back a +list of shares available on the server. +</para> + +<para> +If you get a message <quote><errorname>network name not found</errorname></quote> or similar error, then netbios +name resolution is not working. This is usually caused by a problem in <command>nmbd</command>. +To overcome it, you could do one of the following (you only need to choose one of them): +</para> + +<orderedlist> +<listitem><para> + Fixup the &nmbd; installation. +</para></listitem> + +<listitem><para> + Add the IP address of BIGSERVER to the <command>wins server</command> box in the + advanced TCP/IP setup on the PC. +</para></listitem> + +<listitem><para> + Enable Windows name resolution via DNS in the advanced section of the TCP/IP setup. +</para></listitem> + +<listitem><para> + Add BIGSERVER to your lmhosts file on the PC. +</para></listitem> +</orderedlist> + +<para> +If you get a message <quote><errorname>invalid network name</errorname></quote> or +<quote><errorname>bad password error</errorname></quote>, then apply the +same fixes as for the <command>smbclient -L</command> test above. In +particular, make sure your <command>hosts allow</command> line is correct (see the man pages). +</para> + +<para> +Also, do not overlook that fact that when the workstation requests the +connection to the Samba server, it will attempt to connect using the +name with which you logged onto your Windows machine. You need to make +sure that an account exists on your Samba server with that exact same +name and password. +</para> + +<para> +If you get a message <quote><errorname>specified computer is not receiving requests</errorname></quote> or similar, +it probably means that the host is not contactable via TCP services. +Check to see if the host is running TCP wrappers, and if so add an entry in +the <filename>hosts.allow</filename> file for your client (or subnet, and so on.) +</para> + +</step> + +<step performance="required"> + +<para> +Run the command <command>net use x: \\BIGSERVER\TMP</command>. You should +be prompted for a password, then you should get a <computeroutput>command completed +successfully</computeroutput> message. If not, then your PC software is incorrectly +installed or your &smb.conf; is incorrect. Make sure your <parameter>hosts allow</parameter> +and other config lines in &smb.conf; are correct. +</para> + +<para> +It's also possible that the server can't work out what user name to connect you as. +To see if this is the problem, add the line +<smbconfoption><name>user</name><value>username</value></smbconfoption> to the +<smbconfsection>[tmp]</smbconfsection> section of +&smb.conf; where <parameter>username</parameter> is the +username corresponding to the password you typed. If you find this +fixes things, you may need the username mapping option. +</para> + +<para> +It might also be the case that your client only sends encrypted passwords +and you have <smbconfoption><name>encrypt passwords</name><value>no</value></smbconfoption> in &smb.conf;. +Change this to "yes" to fix this. +</para> + +</step> + +<step performance="required"> + +<para> +Run the command <command>nmblookup -M <parameter>testgroup</parameter></command> where +<parameter>testgroup</parameter> is the name of the workgroup that your Samba server and +Windows PCs belong to. You should get back the IP address of the +master browser for that workgroup. +</para> + +<para> +If you do not, then the election process has failed. Wait a minute to +see if it is just being slow, then try again. If it still fails after +that, then look at the browsing options you have set in &smb.conf;. Make +sure you have <smbconfoption><name>preferred master</name><value>yes</value></smbconfoption> to ensure that +an election is held at startup. +</para> + +</step> + +<step performance="required"> + +<para> +>From file manager, try to browse the server. Your Samba server should +appear in the browse list of your local workgroup (or the one you +specified in &smb.conf;). You should be able to double click on the name +of the server and get a list of shares. If you get the error message <quote>invalid password</quote>, + you are probably running Windows NT and it +is refusing to browse a server that has no encrypted password +capability and is in User Level Security mode. In this case, either set +<smbconfoption><name>security</name><value>server</value></smbconfoption> and +<smbconfoption><name>password server</name><value>Windows_NT_Machine</value></smbconfoption> in your +&smb.conf; file, or make sure <smbconfoption><name>encrypt passwords</name></smbconfoption> is +set to <quote>yes</quote>. +</para> + +</step> +</procedure> +</sect1> + +</chapter> |