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New Member

7975 shows auth fail when it uses SIP and to upgrade its firmware?

I use phone 7975G to register to CUCME by sip.

7975 shows auth fail when it upgrade its firmware?

I changed different firmware version. It still show 'auth fail'. I guess that it's not a firmware version problem.

But what's wrong with my 7975.


please copy paste here config

please copy paste here config for SIP phone

as I know there should be username cisco and password cisco


and dont forget to rate post



voice service voip
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip


#### SIP Phones create Voip Dial-peers. so for SIP to SIP, SIP to H323   you need to allow the connections. SCCP phones create EFXS POTS   dial-peer. By Default IP-IP call is blocked)(Random Fact).
fax protocol pass-through g711ulaw
modem passthrough nse codec g711ulaw
bind control source-interface FastEthernet0/0.426
bind media source-interface FastEthernet0/0.426


### Bind Control and media to the interface with the same IP Address on   source-address x.x.x.x . Else you will run into problems when you try  to  register Phones over a Layer 3 Link.
registrar server


### Needed for phone to register

voice register global
mode cme
### Change mode to CME
source-address port 5060
### Should be the same as bind control and media when you have InterVLAN Routing 
max-dn 10
max-pool 10
authenticate register
### Needed for the phone to authenticate with username password, in intervlan registeration setup
tftp-path flash:
### All the config files for the phones will be stored here.
create profile sync 0174426467043125
### Make sure you enter this command everytime you make some changes.!!!!!! Very IMP!

voice register dn  1
number 1234
### DN for the Phone
voice register pool  1
id mac 0023.5E17.D275
### Mac Address of the Phone trying to register. Which won’t be used an   authentication method when registering in Intervlan register scenario
type 7942
### Make sure you have this in here.! Else SEP<MAC-ADDRESS>.config wouldn’t be created.
number 1 dn 1
### Assigning 1234 to line 1 on the phone
username cisco password cisco
### Credentials the phone uses when it tries to register in case of intervlan.

New Member

Thank you for your reply.It

Thank you for your reply.

It can not upgrade firmware. I have two kinds of ip phones: 9971 and 7975. 9971 works well, but 7975 shows 'Auth fail'.

VIP Gold

Can you attach show run with

Can you attach show run with below debug, and have you tried to factory reset the phone ?

debug ccsip messages

debug tftp events


New Member

Thank you for you reply.

Thank you for you reply.

VIP Gold

Can apply below command under

Can you apply below command under voice register global and then reset the phone.

authenticate realm all

And are you trying to register this phone in different subnet than cme' IP subnet ?


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