Synchronet v3.19b-Win32 (install) has been released (Jan-2022).

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faq:nix [2018/02/13 12:41] – [Ports Below 1024 Without Root On Linux] Add reference to Linux non-root page deucefaq:nix [2020/11/14 11:19] – Create Linux-recycle FAQ digital man
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   * [[#SELinux|What does nothing work with SELinux]]?   * [[#SELinux|What does nothing work with SELinux]]?
   * [[#Disk space|How much disk space is required]]?    * [[#Disk space|How much disk space is required]]? 
-  * [[#TermType|What does an ''unknown terminal'' error indicate]]? +  * [[#Terminal Type|What does an ''unknown terminal'' error indicate]]? 
-  * [[#ports_below_1024_without_root_on_linux|How can I bind to ports below 1024 without being root on Linux]]?+  * [[#tempnam warning|Why do I get a warning about use of ''tempnam'' when compiling]]? 
 +  * [[#SDL Errors|How do I work around SDL 1.2 run-time errors]]? 
 +  * [[#Recycle|Why does the recycling of servers/services not work]]?
      
 ===== Flavors ===== ===== Flavors =====
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 **Answer:**\\    **Answer:**\\   
-A fresh install (as of Feb-2009) requires about 70MBytes. +A fresh install (as of Mar-2020) from source code, requires about 500MBytes of space. 
-Much of the space consumed is in the form of intermediate build files which +Much of the space consumed is in the form of intermediate build files which may be removed after the build is complete if space is a concern.
-may be removed after the build is complete if space is a concern.+
  
  
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 To elaborate, [[util:SBBSecho]] uses ''tempnam'' for a specific purpose, which ''mkstemp'' does not do. Additionally ''mkstemp'' is not available in all the C libraries for all the platforms for which Synchronet is built. The //dangers// of ''tempnam'' do not apply to SBBSecho's use of the function. To elaborate, [[util:SBBSecho]] uses ''tempnam'' for a specific purpose, which ''mkstemp'' does not do. Additionally ''mkstemp'' is not available in all the C libraries for all the platforms for which Synchronet is built. The //dangers// of ''tempnam'' do not apply to SBBSecho's use of the function.
  
-===== Ports Below 1024 Without Root On Linux =====+===== SDL errors =====
 **Question:**\\ **Question:**\\
-How can I bind to network ports below 1024 as a non-root user on Linux?+How do I work around SDL_main errors (e.g. ''No protocol specified'' followed by a ''segmentation fault'') that prevent Synchronet applications (e.g. [[util:SCFG]], [[util:EchoCFG]], [[monitor:umonitor]], etc.) built with SDL 1.2 from running? 
 +<code> 
 +$ /sbbs/exec/scfg 
 +No protocol specified 
 +No protocol specified 
 +No protocol specified 
 +Segmentation fault (core dumped) 
 +</code>
  
 **Answer:**\\ **Answer:**\\
-By default, Linux does not allow non-root processes to bind to ports below 1024.  This was done as a security measure, although some argue that the reasons for this are obsolete.  It is often a bad practice to run processes as root unless it's really necessary to do so, and perhaps even more so with an Internet-accessible server.  Thus, it is often desirable to run servers on standard ports (below 1024) as a non-root user.  You can do so with the setcap command.  For example:\\ +Double check that you can run X applications (e.g. ''xterm'', ''xeyes'') and if you cannot, you may need to grant X access to other user accounts with a command like: 
-  setcap cap_net_bind_service=+ep /sbbs/exec/sbbs+  xhost +SI:localuser:<username> 
 +executed before switching to another user account (e.g. with ''su'' or ''sudo'').
  
-For more information, see the following:\\ +Work-arounds: 
-[[howto:linux_non-root]]\\ +  - Clean re-build all of Synchronet without SDL support (include ''WITHOUT_SDL=1'' on the ''make'' command-lines or in your ''localdefs.mk'' file) 
-[[https://stackoverflow.com/questions/413807/is-there-a-way-for-non-root-processes-to-bind-to-privileged-ports-on-linux|StackOverflow: Is there a way for non-root processes to bind to “privileged” ports on Linux?]]\\ +  - Set the ''SDL_VIDEODRIVER'' environment variable to the value of ''dummy'' (e.g. ''EXPORT SDL_VIDEODRIVER=dummy'') before executing the program 
-[[https://www.jumpingbean.co.za/blogs/mark/run-application-port-below-1024-linux|How to bind to ports below 1024 without being root on Linux?]]\\ + 
-[[https://www.staldal.nu/tech/2007/10/31/why-can-only-root-listen-to-ports-below-1024|Why can only root listen to ports below 1024?]]+===== Recycle ===== 
 +**Question:**\\ 
 +Why do my servers/services fail to recycle when I set the node-recycle flag (e.g. saving changes in [[util:SCFG]]) or when touching [[config:semfiles]]? 
 + 
 +**Question:**\\ 
 +What do the following warning-level log messages indicate? 
 +  Disabling Terminal Server recycle support 
 +  Disabling FTP Server recycle support 
 +  Disabling Web Server recycle support 
 +  Disabling Mail Server recycle support 
 +  Disabling Services recycle support 
 +   
 +**Answer:**\\ 
 +Recycle support can be disabled manually be setting the ''NO_RECYCLE'' ''Options'' flag in one or more server sections of your ''[[config:sbbs.ini]]'' file. The log warning messages above indicate that the BBS automatically set this option flag because it was: 
 +  - Configured to bind-to/listen-on TCP ports < 1024 (the so-called "reserved" ports) 
 +  - **and** the BBS was configured to change the current user-id in the ''[[config:sbbs.ini#UNIX]]'' section of ''[[config:sbbs.ini]]'' 
 +  - **and** the BBS could not dynamically set the bind capabilities using the Linux "Capabilities" syscall interface. 
 + 
 +The solution is to remove the ''User'' and ''Group'' settings from the ''[[config:sbbs.ini#UNIX]]'' section of ''[[config:sbbs.ini]]'' and the follow the instructions [[howto:Linux_non-root|here]] for running the BBS on Linux as a non-root user.
  
 ===== See Also ===== ===== See Also =====

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