Getting Peer hold all free leases
Kraishak Mahtha
kraishak.edu at gmail.com
Tue Aug 17 16:37:45 UTC 2021
Ok Thanks Bob
On Tue, 17 Aug 2021, 22:03 Bob Harold, <rharolde at umich.edu> wrote:
> I have not figured out any cause. But it has been happening somewhat
> randomly for years. I did not open a case with ISC, so partly my fault.
> With the work on Kea, I don't know if they would have time to fix DHCPD
> at this point.
>
> --
> Bob Harold
> DNS and DHCP Hostmaster - UMNet
> Information and Technology Services (ITS)
> rharolde at umich.edu
>
>
> On Tue, Aug 17, 2021 at 12:11 PM Kraishak Mahtha <kraishak.edu at gmail.com>
> wrote:
>
>> Hi Bob,
>>
>> Thanks for sharing your experience and work case for fixing the issue,
>> Yes It worked for me too, removed the failover for that specific subnet and
>> then started dhcpd on both the appliances then added it back again now
>> everything looks good
>>
>> With lots of subnets, all using failover, I see this error fairly often
>> ---->Bob, do you observe/feel any common steps in your environment which
>> might trigger this type of issue ? Just want to know what triggered this
>> inconsistency in the lease file
>>
>> Thanks for quick responses to all
>>
>> On Tue, Aug 17, 2021 at 7:39 PM Bob Harold <rharolde at umich.edu> wrote:
>>
>>> With lots of subnets, all using failover, I see this error fairly
>>> often. I am using a vendor IPAM solution, so my fix is to remove the
>>> failover server from the subnet config, push out new dhcpd.conf files, then
>>> put it back and push again. Under the covers, that actually does:
>>> - Remove the subnet completely from the second server, and reload
>>> dhcpd. The server will drop all the leases for that subnet since the
>>> subnet is gone.
>>> - Remove the "failover" line for that subnet on the primary server and
>>> reload dhcp.
>>> - Add the failover line back in and reload the primary.
>>> - Add the subnet to the secondary again.
>>>
>>> That is what works for me.
>>>
>>> --
>>> Bob Harold
>>> DNS and DHCP Hostmaster - UMNet
>>> Information and Technology Services (ITS)
>>> rharolde at umich.edu
>>>
>>>
>>> On Tue, Aug 17, 2021 at 9:57 AM Abdul Khader <akhader at gmail.com> wrote:
>>>
>>>> Hi Kraishak
>>>> Check the communication is happening on port 647 on both the servers
>>>> using tcpdump -i any port 647
>>>> Please also check if there are multiple entries my state and partner
>>>> state. Feel both the servers are not in sync. Can you also check if the
>>>> discovers from client is landing on both the servers ? If you are using
>>>> split 128 then the traffic should land on both the Nodes. Check your ip
>>>> helper (relay) to make sure it's configured to send to both the Nodes.
>>>>
>>>> Regards
>>>>
>>>>
>>>> On Tue, 17 Aug 2021, 17:11 Kraishak Mahtha, <kraishak.edu at gmail.com>
>>>> wrote:
>>>>
>>>>> Hi Abdul Khader,
>>>>>
>>>>> I have declared as follows:
>>>>>
>>>>> Configuration file from primary
>>>>> =========================
>>>>> failover peer "peer-host" {
>>>>> primary;
>>>>> address 192.168.56.156;
>>>>> port 647;
>>>>> peer address 192.168.56.178;
>>>>> peer port 647;
>>>>> max-response-delay 30;
>>>>> max-unacked-updates 30;
>>>>> load balance max seconds 3;
>>>>> mclt 1800;
>>>>> split 128;
>>>>> }
>>>>> subnet 192.168.56.0 netmask 255.255.255.0 {
>>>>> pool {
>>>>> failover peer "peer-host";
>>>>> range 192.168.56.5 192.168.56.54;
>>>>> }
>>>>> option domain-name "test.com";
>>>>> option routers 192.168.56.1;
>>>>> option subnet-mask 255.255.255.0;
>>>>> }
>>>>>
>>>>> Configuration file from failover
>>>>> ======================
>>>>> failover peer "peer-host" {
>>>>> secondary;
>>>>> address 192.168.56.178;
>>>>> port 647;
>>>>> peer address 192.168.56.156;
>>>>> peer port 647;
>>>>> max-response-delay 30;
>>>>> max-unacked-updates 30;
>>>>> load balance max seconds 3;
>>>>> }
>>>>> subnet 192.168.56.0 netmask 255.255.255.0 {
>>>>> pool {
>>>>> failover peer "peer-host";
>>>>> range 192.168.56.5 192.168.56.54;
>>>>> }
>>>>> option domain-name "test.com";
>>>>> option routers 192.168.56.1;
>>>>> option subnet-mask 255.255.255.0;
>>>>> }
>>>>>
>>>>> On the primary log it shows as :* total 50 free 0 backup 0*
>>>>> *Aug 17 17:15:48 dhcp1 dhcpd[12130]: peer peer-host: Got POOLREQ,
>>>>> answering negatively! Peer may be out of leases or database inconsistent.*
>>>>>
>>>>> but in the failover log it shows as
>>>>> Aug 17 17:14:48 dhcp2 dhcpd[1902]: balancing pool bf05b0
>>>>> 192.168.56.0/24 *total 50 free 50 backup 0 lts -25 max-own
>>>>> (+/-)5 * (requesting peer rebalance!)
>>>>> Aug 17 17:14:48 dhcp2 dhcpd[1902]: balanced pool bf05b0
>>>>> 192.168.56.0/24 total 50 free 50 backup 0 lts -25 max-misbal 8
>>>>> pool response: 0 leases
>>>>>
>>>>> because of some reason the pool is not getting balanced between the
>>>>> primary and failover
>>>>>
>>>>>
>>>>> Also I have a problem in tracking my thread previously from *http://isc-dhcp-users
>>>>> <http://isc-dhcp-users>* link I used to track and reply but now it is
>>>>> not working, and tried searching the other links I found this *https://lists.isc.org/pipermail/dhcp-users/
>>>>> <https://lists.isc.org/pipermail/dhcp-users/> *to track but I cannot
>>>>> see a reply option in that web page
>>>>>
>>>>>
>>>>>
>>>>> On Tue, Aug 17, 2021 at 5:41 PM Kraishak Mahtha <
>>>>> kraishak.edu at gmail.com> wrote:
>>>>>
>>>>>> Hi,
>>>>>> I am using ISC DHCP in primary and failover mode and I am getting
>>>>>> issue that clients are not getting leases and when I checked for the
>>>>>> service logs I see as
>>>>>> Primary Logs:
>>>>>> ==========
>>>>>> Aug 17 17:15:48 dhcp1 dhcpd[12130]: balancing pool f6f5f0
>>>>>> 192.168.56.0/24 total 50 free 0 backup 0 lts 0 max-own (+/-)0
>>>>>> Aug 17 17:15:48 dhcp1 dhcpd[12130]: balanced pool f6f5f0
>>>>>> 192.168.56.0/24 total 50 free 0 backup 0 lts 0 max-misbal 0
>>>>>> Aug 17 17:15:48 dhcp1 dhcpd[12130]: peer peer-host: Got POOLREQ,
>>>>>> answering negatively! Peer may be out of leases or database inconsistent.
>>>>>>
>>>>>> Failover Logs
>>>>>> ==========
>>>>>> Aug 17 17:14:48 dhcp2 dhcpd[1902]: balancing pool bf05b0
>>>>>> 192.168.56.0/24 total 50 free 50 backup 0 lts -25 max-own
>>>>>> (+/-)5 (requesting peer rebalance!)
>>>>>> Aug 17 17:14:48 dhcp2 dhcpd[1902]: balanced pool bf05b0
>>>>>> 192.168.56.0/24 total 50 free 50 backup 0 lts -25 max-misbal 8
>>>>>> pool response: 0 leases
>>>>>>
>>>>>> I tried searching the forums and many of them suggested that there
>>>>>> might be inconsistency between the configuration file and leases database,
>>>>>> I cross verified the configs they are good and regarding the leases file
>>>>>> can we manually do any operation to make them in sync ?
>>>>>>
>>>>>> I tried checking the status of the primary and failover in the lease
>>>>>> file but they are in normal-normal,
>>>>>> cat dhcpd.leases | egrep "my state|partner state" | tail -2
>>>>>> my state normal at 2 2021/08/17 16:41:09;
>>>>>> partner state normal at 2 2021/08/17 17:01:17;
>>>>>>
>>>>>> Has anyone faced a similar issue/Any suggestions of how to fix the
>>>>>> issue,
>>>>>> Can we manually send requests for the DHCP service to do the pool
>>>>>> balance and sync the leases for that specific subnet ?
>>>>>>
>>>>>>
>>>>>> Any help/suggestion would be much appreciated
>>>>>> Thanks
>>>>>> Kraishak
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>> ISC funds the development of this software with paid support
>>>> subscriptions. Contact us at https://www.isc.org/contact/ for more
>>>> information.
>>>>
>>>> dhcp-users mailing list
>>>> dhcp-users at lists.isc.org
>>>> https://lists.isc.org/mailman/listinfo/dhcp-users
>>>>
>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.isc.org/pipermail/dhcp-users/attachments/20210817/a2ae298e/attachment-0001.htm>
More information about the dhcp-users
mailing list