Cannot Save Configuration after the IP is Assigned by DHCP server (SG300-20)

[felixmarch]

Dear Support,

We bought Cisco SG300-20 (firmware revision: 1.0.0.27) and observed an issue when saving the configuration with the dynamic IP.

• Whenever the switch is plugged into the network that has DHCP server, by default the switch will automatically change its IP by itself from Static (192.168.1.254) to Dynamic.
• Once the IP is changed to dynamic, we will not be able to save any configuration and get error message: "Another copy process is active, please try again later" (please see the screenshot in the attachment)
  

We browsed the release notes (http://www.cisco.com/en/US/products/ps10898/prod_release_notes_list.html), but cannot find any info there.

We also cannot change back the IP from dynamic back to static 192.168.1.254 due to another issue highlighted in the CQ 122633's release notes.

Kindly advise.

Thanks.

[brianvans]

Do the logs show the switch is picking up what it thinks is a configuration file via TFTP?

I recently encountered a similar issue with deploying a few SG-300-52's.  If the DHCP server in question is offering a bootfile for PXE booting, the switch will try and parse it, thinking it's a valid configuration file.  This seems to confuse the switch badly and break many of the file operations, including copying running-config to startup-config.

Reset the switch to factory defaults and disable DHCP auto configuration (Administration->File Management) before putting the switch anywhere near your DHCP server.  I also denied outbound TFTP packets to my switches IPs from our TFTP/PXE bootrom server for good measure.

Hope this helps.

[felixmarch]

Thank you Brian, for the info and the clue.

Yes, from the log, I saw the tftp error message:

2147483588     2010-Apr-28 13:35:31    Note     %SYSLOG-N-LOGGING: Logging started.
2147483589     2010-Apr-28 13:34:48    Alert     %TFTP-A-TftpTxERROR: An error message was sent: 0
2147483590     2010-Apr-28 13:34:46    Informational     %COPY-I-FILECPY: Files Copy - source URL tftp://192.168.1.253//vmlinuz-tray-ramdisk.0.1.0 destination URL flash://startup-config
2147483591     2010-Apr-28 13:34:46    Informational     %BOOTP_DHCP_CL-I-DHCPCONFIGURED: The device has been configured on interface Vlan 1 , IP 192.168.1.233, mask 255.255.255.0, DHCP server 192.168.1.253
2147483592     2010-Apr-28 13:34:46    Informational     %BOOTP_DHCP_CL-I-BOOTPCONFIGURED: The device has been configured via BOOTP

Disabling the DHCP auto configuration before putting the switch into the DHCP system, is not a feasible option for my system here (because there are more than 100+ systems in my factory and they are built by external parties with complex logistics).

As you mentioned the switch would try to parse the bootfile from PXE thinking it is a configuration file, I tried to modify the dhcpd.conf in the DHCP server to give a valid config file.

With correct config file on the DHCP server, it seems the error has gone away.
I will do more testing on tweaking this dhcp and the config file.

It would be good if Cisco can document this startup behavior from the beginning !
This can really prevent the users on troubleshooting the system all the day  just to figure out of what's wrong and what happens on the DHCP vs static ...

To share my config that I had just tried:

/etc/dhcpd.conf:

class "ciscosg300" {
    match if substring(hardware,1,4) = 68:bd:ab:0e;
    filename "/disabled-dhcp.txt";
}

subnet 192.168.1.0 netmask 255.255.255.0 {
    ...
    ...
    ...
}

/tftpboot/disabled-dhcp.txt:

voice vlan oui-table add 0001e3 Siemens_AG_phone________
voice vlan oui-table add 00036b Cisco_phone_____________
voice vlan oui-table add 00096e Avaya___________________
voice vlan oui-table add 000fe2 H3C_Aolynk______________
voice vlan oui-table add 0060b9 Philips_and_NEC_AG_phone
voice vlan oui-table add 00d01e Pingtel_phone___________
voice vlan oui-table add 00e075 Polycom/Veritel_phone___
voice vlan oui-table add 00e0bb 3Com_phone______________
interface vlan 1
no ip address dhcp
exit
no ip dhcp autoconfig
bonjour service enable csco-sb
bonjour service enable http
bonjour service enable https
bonjour service enable ssh
bonjour service enable telnet
hostname ciscosg300
username cisco password da39a3ee5e6b4b0d3255bfef95601890afd80709 level 15 encrypted
no snmp-server enable

[gloidl]

Hi Felix,

I tried in our lab to recreate your situation but could not generate the same error message you experienced.

However, I came across this support posting which seems to mirror the problem you have.

Can you please try to remove option 67 on your DHCP server. Please refer to the articles in question.

message ID 3304670

Hope this helps