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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I’ve already posted this to the user’s
mailing list, but I think that here is a best place for this. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I’ve noticed that rlm_ippool is nearly always
reassigning an IP address that has just been releasing for a new connexion. This
causes some TCP connexion problems because of the TIME_WAIT state. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Scenario:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>1/ one device connects using source port 1024 (ppp)
and gets an IP address from freeradius<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>2/ this device disconnects, the ip is freed from the
pool<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>3/ another devices connects using source port 1024
and gets the same ip address as before<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>4/ the connexion is impossible to the server because
the connexion of last device is still in TIME_WAIT state<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>How can I make sure an IP address is not assigned
before some time period (240 seconds, time period of the TIME_WAIT state) after
being released? <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I got one answer :<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>>Interesting.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>>The IPs are allocated
by a GDBM walk of the database, and use of the first free or expired IP. This
will always tend to be the same one hence the repeat >allocations.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>>It would in theory be
possible to save the key from the last walk, and next time we allocate an IP
start from that key and wrap back around, which would >allocate IPs in a
more round-robin fashion.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>I would appreciate if
someone can help doing the hack or give me some hints to modify rlm_ippool.c to
add some retention time parameter to make sure an ip is not reassigned
instantly after being freed or to make things work more in a random or round
robin way. <o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Thanks in advance. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Regards,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Sebastien. <o:p></o:p></span></font></p>
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