修改admin的加密密码为123456的加密密码
#jbcrypt:$2a$10$MiIVR0rr/UhQBqT.bBq0QehTiQVqgNpUGyWW2nJObaVAM/2xSQdSq
vim /root/.jenkins/users/admin/config.xml <hudson.security.HudsonPrivateSecurityRealm_-Details>
<passwordHash>#jbcrypt:$2a$10$MiIVR0rr/UhQBqT.bBq0QehTiQVqgNpUGyWW2nJObaVAM/2xSQdSq</passwordHash>
</hudson.security.HudsonPrivateSecurityRealm_-Details>
修改保存之后，再重启jenkins即可