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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">this is just a quick shout back - please forgive my not checking the math, but at first glance this doesn't look like the right mask.<br>
<br>
<span class="824125613-08092011"><font face="Arial" size="2"> subnet 123.123.226.192 netmask 255.255.255.224 {</font></span><br>
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<div><font face="Tahoma" size="2">Randall Grimshaw <a href="mailto:rgrimsha@syr.edu">
rgrimsha@syr.edu</a></font></div>
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<div style="direction: ltr;" id="divRpF412589"><font color="#000000" face="Tahoma" size="2"><b>From:</b> dhcp-users-bounces+rgrimsha=syr.edu@lists.isc.org [dhcp-users-bounces+rgrimsha=syr.edu@lists.isc.org] on behalf of Fredrik Björk [fredrik.bjork@fiberdata.se]<br>
<b>Sent:</b> Thursday, September 08, 2011 10:30 AM<br>
<b>To:</b> dhcp-users@lists.isc.org<br>
<b>Subject:</b> dhcpd handing out wrong gateway<br>
</font><br>
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<div><span class="824125613-08092011"><font face="Arial" size="2">Hi!</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
<div><span class="824125613-08092011"><font face="Arial" size="2">We're having occasional problems with ISC dhcpd handing out an incorrect gateway (option routers) to some clients. This happens only for specific clients and is more or less persistent for those.
The config is somewhat complicated and involves a few shared networks.</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
<div><span class="824125613-08092011">
<div><span class="824125613-08092011"><font face="Arial" size="2">What happens is that a client in network 123.123.230.0/24 gets a correct IP, the appropriate subnet mask and all other options, but the gateway is 123.123.235.1, which is in a totally different
subnet and even another shared network! Anybody with a clue about what's going on out there?</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
</span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">Just to give you a rough idea on the structure, I've filtered out a few lines from the config:</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
<div><span class="824125613-08092011"><font face="Arial" size="2">shared-network eth0{<br>
subnet 192.168.20.0 netmask 255.255.255.0 {<br>
subnet 123.123.224.0 netmask 255.255.255.0 {<br>
subnet 123.123.236.0 netmask 255.255.255.0 {<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">shared-network BSR1CM {<br>
subnet 172.16.0.0 netmask 255.255.252.0 {<br>
subnet 172.16.8.0 netmask 255.255.255.0 {<br>
shared-network BSR1CPE {<br>
subnet 123.123.225.0 netmask 255.255.255.0 {<br>
subnet 123.123.226.0 netmask 255.255.255.128 {<br>
subnet 123.123.226.128 netmask 255.255.255.192 {<br>
subnet 123.123.226.192 netmask 255.255.255.224 {<br>
shared-network BSR1MTA {<br>
subnet 123.123.226.224 netmask 255.255.255.224 {<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">shared-network BSR2CM {<br>
subnet 172.17.0.0 netmask 255.255.252.0 {<br>
subnet 172.17.4.0 netmask 255.255.252.0 {<br>
subnet 172.17.8.0 netmask 255.255.252.0 {<br>
shared-network BSR2CPE {<br>
subnet 123.123.227.0 netmask 255.255.255.0 {<br>
subnet 123.123.228.0 netmask 255.255.255.128 {<br>
subnet 123.123.228.128 netmask 255.255.255.192 {<br>
subnet 123.123.228.192 netmask 255.255.255.224 {<br>
subnet 123.123.228.224 netmask 255.255.255.224 {<br>
shared-network BSR2MTA {<br>
subnet 123.123.229.0 netmask 255.255.255.0 {<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">shared-network BSR3CM {<br>
subnet 172.18.0.0 netmask 255.255.252.0 {<br>
subnet 172.18.4.0 netmask 255.255.252.0 {<br>
subnet 172.18.8.0 netmask 255.255.252.0 {<br>
shared-network BSR3CPE {<br>
subnet 123.123.230.0 netmask 255.255.255.0 {<br>
subnet 123.123.233.0 netmask 255.255.255.0 {<br>
subnet 123.123.231.0 netmask 255.255.255.0 {<br>
shared-network BSR3MTA {<br>
subnet 123.123.232.0 netmask 255.255.255.0 {<br>
subnet 123.123.234.0 netmask 255.255.255.0 {<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">shared-network CASACM {<br>
subnet 172.19.0.0 netmask 255.255.240.0 {<br>
shared-network CASACPE {<br>
subnet 123.123.235.0 netmask 255.255.255.0 {<br>
subnet 123.123.237.0 netmask 255.255.255.0 {<br>
subnet 123.123.238.0 netmask 255.255.255.0 {<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
<div><span class="824125613-08092011"><font face="Arial" size="2">14:29:20.933479 IP (tos 0x0, ttl 255, id 5252, offset 0, flags [none], proto UDP (17), length 344) 123.123.230.1.68 > 123.123.224.<br>
42.67: BOOTP/DHCP, Request from 00:19:99:a0:51:13, length 316, hops 1, xid 0x39e50835, Flags [none]<br>
Gateway-IP 123.123.230.1<br>
Client-Ethernet-Address 00:19:99:a0:51:13<br>
Vendor-rfc1048 Extensions<br>
Magic Cookie 0x63825363<br>
DHCP-Message Option 53, length 1: Discover<br>
Client-ID Option 61, length 7: ether 00:19:99:a0:51:13<br>
Requested-IP Option 50, length 4: 123.123.233.232<br>
Hostname Option 12, length 12: "MyRouter"<br>
Vendor-Class Option 60, length 8: "MSFT 5.0"<br>
Parameter-Request Option 55, length 12:<br>
Subnet-Mask, Domain-Name, Default-Gateway, Domain-Name-Server<br>
Netbios-Name-Server, Netbios-Node, Netbios-Scope, Router-Discovery<br>
Static-Route, Classless-Static-Route, Classless-Static-Route-Microsoft, Vendor-Option<br>
Agent-Information Option 82, length 14:<br>
Unknown SubOption 2, length 6:<br>
0x0000: 0013 71e7 68ee<br>
Unknown SubOption 43, length 4:<br>
0x0000: ac12 03f5<br>
14:29:21.001405 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 335) 123.123.224.42.67 > 123.123.230.1.67:<br>
BOOTP/DHCP, Reply, length 307, hops 1, xid 0x39e50835, Flags [none]<br>
Your-IP 123.123.233.232<br>
Server-IP 123.123.224.42<br>
Gateway-IP 123.123.230.1<br>
Client-Ethernet-Address 00:19:99:a0:51:13<br>
Vendor-rfc1048 Extensions<br>
Magic Cookie 0x63825363<br>
DHCP-Message Option 53, length 1: Offer<br>
Server-ID Option 54, length 4: 123.123.224.42<br>
Lease-Time Option 51, length 4: 600<br>
Subnet-Mask Option 1, length 4: 255.255.255.0<br>
Domain-Name Option 15, length 11: "sweden.se"<br>
Default-Gateway Option 3, length 4: 123.123.235.1 <<<<----- WRONG!<br>
Domain-Name-Server Option 6, length 8: 213.50.29.170,208.67.222.222<br>
Agent-Information Option 82, length 14:<br>
Unknown SubOption 2, length 6:<br>
0x0000: 0013 71e7 68ee<br>
Unknown SubOption 43, length 4:<br>
0x0000: ac12 03f5<br>
14:29:21.016281 IP (tos 0x0, ttl 255, id 5256, offset 0, flags [none], proto UDP (17), length 364) 123.123.230.1.68 > 123.123.224.42.67: BOOTP/DHCP, Request from 00:19:99:a0:51:13, length 336, hops 1, xid 0x39e50835, Flags [none]<br>
Gateway-IP 123.123.230.1<br>
Client-Ethernet-Address 00:19:99:a0:51:13<br>
Vendor-rfc1048 Extensions<br>
Magic Cookie 0x63825363<br>
DHCP-Message Option 53, length 1: Request<br>
Client-ID Option 61, length 7: ether 00:19:99:a0:51:13<br>
Requested-IP Option 50, length 4: 123.123.233.232<br>
Server-ID Option 54, length 4: 123.123.224.42<br>
Hostname Option 12, length 12: "MyRouter"<br>
FQDN Option 81, length 15: "MyRouter"<br>
Vendor-Class Option 60, length 8: "MSFT 5.0"<br>
Parameter-Request Option 55, length 12:<br>
Subnet-Mask, Domain-Name, Default-Gateway, Domain-Name-Server<br>
Netbios-Name-Server, Netbios-Node, Netbios-Scope, Router-Discovery<br>
Static-Route, Classless-Static-Route, Classless-Static-Route-Microsoft, Vendor-Option<br>
Agent-Information Option 82, length 14:<br>
Unknown SubOption 2, length 6:<br>
0x0000: 0013 71e7 68ee<br>
Unknown SubOption 43, length 4:<br>
0x0000: ac12 03f5<br>
14:29:21.017506 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 335) 123.123.224.42.67 > 123.123.230.1.67: BOOTP/DHCP, Reply, length 307, hops 1, xid 0x39e50835, Flags [none]<br>
Your-IP 123.123.233.232<br>
Server-IP 123.123.224.42<br>
Gateway-IP 123.123.230.1<br>
Client-Ethernet-Address 00:19:99:a0:51:13<br>
Vendor-rfc1048 Extensions<br>
Magic Cookie 0x63825363<br>
DHCP-Message Option 53, length 1: ACK<br>
Server-ID Option 54, length 4: 123.123.224.42<br>
Lease-Time Option 51, length 4: 600<br>
Subnet-Mask Option 1, length 4: 255.255.255.0<br>
Domain-Name Option 15, length 11: "sweden.se"<br>
Default-Gateway Option 3, length 4: 123.123.235.1<br>
Domain-Name-Server Option 6, length 8: 213.50.29.170,208.67.222.222<br>
Agent-Information Option 82, length 14:<br>
Unknown SubOption 2, length 6:<br>
0x0000: 0013 71e7 68ee<br>
Unknown SubOption 43, length 4:<br>
0x0000: ac12 03f5<br>
</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2">Any help is much appreciated!</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"></font></span> </div>
<div><span class="824125613-08092011"><font face="Arial" size="2">/Fredrik</font></span></div>
<div><span class="824125613-08092011"><font face="Arial" size="2"> </font></span></div>
<font face="Arial" size="2"></font></div>
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